ECOLOGY AND ENERGY PRODUCTION

ECOLOGY AND ENERGY PRODUCTION

Friday, July 31, 2015

GCSE results are down to your GENES:A magic eye?

 

 

 

 

 

GCSE results are down to your GENES: DNA plays a bigger part in exam success than school and home life combined

  • Data from 12,500 identical and non-identical twins was analysed
  • Between 54-65 per cent of GCSE results are down to genes we inherit
  • When intelligence was taken into account genetics still played a major role
  • Teaching methods in the future could take into account genetic factors

Across Britain, teenagers are awaiting nervously for their GCSE results to arrive next month.

But however they fare, they can put some of their grades down to their parents, scientists suggest.

In what is likely to further fuel the endless nature versus nurture debate, researchers found between 54-65 per cent of GCSE results are down to nature – the genes we inherit.

Nature vs nurture: In what is likely to further fuel the endless nature versus nurture debate, researchers found between 54-65 per cent of GCSE results are down to the genes we inherit (file image)

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Nature vs nurture: In what is likely to further fuel the endless nature versus nurture debate, researchers found between 54-65 per cent of GCSE results are down to the genes we inherit (file image)

Genes were more important than the role played by the home and school combined. Home was responsible for 14 per cent of GCSE results and school quality 21 per cent.

The new research showed the same genes affect performance across a much wider spectrum of subjects than just English, Maths and Science, which earlier research found to be about 60 per cent down genetically decided.

Genetic factors also affected results in history and geography, second languages, business studies, computing, art and drama, the researchers found.

Scientists from King's College London analysed genetic data from 12,500 identical and non-identical twins to assess the importance of genetic factors in academic achievement.

GCSE SUCCESS IS IN YOUR GENES

The new research showed the same genes affect performance across a much wider spectrum of subjects than just English, Maths and Science, which earlier research found to be about 60 per cent down genetically decided.

Genetic factors also affected results in history and geography, second languages, business studies, computing, art and drama, the researchers found.

Scientists from King's College London analysed genetic data from 12,500 identical and non-identical twins to assess the importance of genetic factors in academic achievement.

Surprisingly, when the data was analysed and intelligence was stripped out of the results, genetics still played a major role in GCSE performance – accounting for a lower percentage, but still between 45 per cent and 58 per cent of exam results.

Each twin pair grew up in the same home and attended the same schools, so the researchers could take environmental impact to be constant.

They then compared the GCSE results of the identical twins - who share 100 per cent of their genes - with those of the non-identical twins - who share only 50 per cent of their genes.

By comparing the two sets and subtracting the impact of environment, the scientists disentangled the comparative weight of nature and nurture on the GCSE scores.

The twins were also tested for intelligence to see what role it played in GCSE results. Intelligence is highly heritable – if our parents are bright sparks, we are likely to be as well.

Surprisingly, when the data was analysed and intelligence was stripped out of the results, genetics still played a major role in GCSE performance – accounting for a lower percentage, but still between 45 per cent and 58 per cent of exam results.

The researchers suggest this is because other factors – which also have a high genetic component – such as personality and motivation may be playing a role in exam scores.

Dr Rimfeld said: 'Our findings suggest that many of the same genes influence achievement across a broad range of disciplines, moving beyond core subjects such as English and maths to include humanities, business, art and languages.

'For the first time, we found that these general genetic effects on academic achievement remained even when the effects of general intelligence were removed.'

Scientists from King’s College London analysed genetic data from 12,500 identical and non-identical twins to assess the importance of genetic factors in academic achievement (file image)

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Scientists from King's College London analysed genetic data from 12,500 identical and non-identical twins to assess the importance of genetic factors in academic achievement (file image)

She added: 'What does it all mean? These results don't have specific implications for teachers in the classroom right now but they do add to the knowledge of why children do differ so widely in their educational achievement.'

The researchers say in the future, educational techniques could take into account genetic factors.

Robert Plomin, another of the study's authors said understanding which genetic factors influence education could lead to 'educationalists develop effective personalised learning programmes, to help every child reach their potential by the end of compulsory education.'

Teachers, however, greeted the study with caution.

Christine Blower, General Secretary of the National Union of Teachers, said: 'Teachers remain committed to the idea that all students are capable of success, and that low expectations – easily derived from research like this – are a major obstacle to such success.'

Prof John Hardy, Professor of Neuroscience, UCL, said: 'Twin studies are a mainstay of behavioural genetics, but they make a simple assumption that is unlikely to be true: that is that we treat identical twins the same as we treat non-identical twins (who look much more different from each other).

'These results are interesting, therefore, but by no means definitive and it would be unwise to make educational decisions based on these data.'

Professor Timothy Spector, Professor of Genetic Epidemiology, King's College London, said: 'Studies showing exam achievements (like IQ) have a strong genetic influence are not new. Unfortunately they are usually over-interpreted as presenting falsely a notion of fixed destiny.'

 

 

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A magic eye? No, these incredible images reveal the secrets of how the cells in our retina collect information to let us SEE

  • Thousands of video gamers have used an online programme to help scientists map neurons in retinas
  • The game they are playing is EyeWire, which launched in 2012 and has over 120,000 gamers across 100 countries
  • While playing users work together to 'trace' the paths of neurons throughout 3D representations of cells
  • In this instance the information was used to see how information is transmitted from the eye to the brain
  • But in future the game could be used to map other brain functions such as how smells are linked to emotions

Hundreds of thousands of video gamers are right now plugged into one computer game.

But it’s not the latest Call of Duty or Fifa – it’s a science based game called EyeWire in which users map the neurons of a brain.

And information collected from the gamers using the crowdsourcing programme has been used to map neurons in an eye’s retina for the first time.

An online video game known as EyeWire has been used to help map the neurons in the retina of a mouse, which can in turn be applied to that of a human. Outlined in the journal Nature, the study relied on information crowdsourced by thousands of gamers. The popular game has been running since late 2012 and shows how games can be used to help research in various branches of science. In this image, different cells in the retina have been traced in various colours by gamers

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An online video game known as EyeWire has been used to help map the neurons in the retina of a mouse, which can in turn be applied to that of a human. Outlined in the journal Nature, the study relied on information crowdsourced by thousands of gamers. The popular game has been running since late 2012 and shows how games can be used to help research in various branches of science. In this image, different cells in the retina have been traced in various colours by gamers

The findings were announced in the journal nature by a team including Professor Sebastian Seung of the Massachusetts Institute of Technology (MIT).

HOW THE EYE SEES

Light from an object passes through your pupil into your eye.

Depending on how bright the light is, your iris changes size.

The lens then focuses this light onto the your retina at the back of your eye.

The retina is composed of light-sensitive neurons known as photoreceptors that change light signals into electrical signals.

These are then transmitted to the brain where an image is formed.

Professor Seung’s lab at MIT has been running the hugely popular EyeWire game since late 2012, which contributed to the study.

The latest discovery is a huge boon for the game and shows how useful crowdsourcing can be in various branches of science.

In the game, players are given layers of a a retina - in this case one of a mouse - which is similar to a human’s in many ways.

By making a plastic print of a retina, a 3D replication is made on a computer screen.

Gamers are then tasked with individually mapping out the neurons by scrolling up and through the various layers.

In EyeWire, users are given blocks of cells within a retina of a mouse that has been moulded in plastic and scanned into the system. Gamers then intricately study the layers of cells and trace out the paths of neurons. Together, with multiple gamers tackling the same section, an accurate map of the neuron is made and a 3D representation, as seen in this image, can be made. Here in yellow-green is a starburst amacrine cell, while in blue is a single bipolar

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In EyeWire, users are given blocks of cells within a retina of a mouse that has been moulded in plastic and scanned into the system. Gamers then intricately study the layers of cells and trace out the paths of neurons. Together, with multiple gamers tackling the same section, an accurate map of the neuron is made and a 3D representation, as seen in this image, can be made. Here in yellow-green is a starburst amacrine cell, while in blue is a single bipolar

Multiple users tackle different parts of the membrane and, to eliminate errors, some map the same cells as others.

As neurons are mapped, gamers gain points, with expert users going keeping an eye on things in case mistakes are made.

The game doesn’t require users to have any background in biology though, allowing anyone to pick up and get involved with the project.

‘You no longer have to have a PhD in neuroscience,’ said Amy Robinson, creative director of EyeWire, told NBC News. ‘You could be a high-school student, or a sculptor, a dental assistant or retiree. All you have to have is now an Internet connection and an interest in gaming.’

Over 120,000 gamers have signed up from 100 countries to play EyeWire.

But to solve this particular retina challenge, a selection of just over 2,000 of the best ‘EyeWirers’ mapped the so-called starburst amacrine cells, which are found in the retina, and they are all listed as co-authors on the paper.

The EyeWire team are now looking at new challenges for their gamers to overcome.

These include taking a look at the connections between smells and emotional responses.

Here another starburst amacrine cell is shown in red, along with three bipolar cells. Starburst cells are used by retinas for selecting a direction to look, and they also help retinas develop over time. Bipolar cells, meanwhile, act as signal couriers between photoreceptors (which gather light) and ganglion cells that take the signals into the cortex of the brain. Aside from retinas, it is hoped that future EyeWire projects will map other functions of the brain as well

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Here another starburst amacrine cell is shown in red, along with three bipolar cells. Starburst cells are used by retinas for selecting a direction to look, and they also help retinas develop over time. Bipolar cells, meanwhile, act as signal couriers between photoreceptors (which gather light) and ganglion cells that take the signals into the cortex of the brain. Aside from retinas, it is hoped that future EyeWire projects will map other functions of the brain as well

 

Scientists have created a comprehensive and interactive 'atlas of the brain' - and have opened it up to the entire internet to help in neurological research.

The atlas was created from the scans of three 'clinically unremarkable' brains - donated following the deaths of a 24-year-old and 39-year-old man, and half a brain from a third man.

A 3D rendering by the Allen Institute shows genes within the internal structure of the brain: Blue dots show low gene activity, red dots show high activity

A 3D rendering by the Allen Institute shows genes within the internal structure of the brain: Blue dots show low gene activity, red dots show high activity

There are more than 20,000 genes in the human genome, and around 84 per cent of them are active within the human brain.

To create the atlas, the scientists first of all scanned the brains, before chopping them into small pieces. For each piece, they scanned for and recorded the activity levels of the 20,000 genes.

When the scans of the two complete brains were compared to each other, the team found what they believe is a 'genetic blueprint' for how the brain may be mapped out - with so many similarities in gene placement and usage.

Their next aim is to scan a female brain to see how it compares to the other gender.

Mapping: Scientists spent four years on the $50m project to link a number of genes with the site on the brain that they correspond to

Mapping: Scientists spent four years on the $50m project to link a number of genes with the site on the brain that they correspond with

Professor Seth Grant of Edinburgh University, who helped create the map, said: 'The human brain is the most complex structure known to mankind and one of the greatest challenges in modern biology is to understand how it is built and organised.

'This allows us for the first time to overlay the human genome on to the human brain.

'It gives us essentially the Rosetta stone for understanding the link between the genome and the brain, and gives us a path forward to decoding how genetic disorders impact and produce brain disease.'

Brain matter: Scientists hope that by creating a digital map of the brain they will be able to better understand a range on conditions and how they develop

Brain matter: Scientists hope that by creating a digital map of the brain they will be able to better understand a range on conditions and how they develop

It is commonly-known that people use each side of the brain for different purposes, with 'creative' tasks coming from the right side of the brain. However researchers saw no such divide within genes, suggesting another mechanism controls how we handle different tasks.

With the map available to the public at http://human.brain-map.org, it is hoped that other researchers can compare their gene research against the atlas, improving our knowledge of our most vital organ.

Institutes such as Max Planck Institute for Psycholinguistics have already announced they will use the map to help research genes and brain symmetry. More than other 4,000 researchers have already used the tool.

Brain scans which establish how well different regions of your brain are detected may be able to predict how intelligent you are, a new study claims.

Research suggests that 10 per cent of individual differences in intelligence can be explained by the strength of neural pathways connecting the left lateral prefrontal cortex to the rest of the brain.

The findings, published in the Journal of Neuroscience, establish 'global brain connectivity' as a new approach for understanding how human intelligence relates to physiology.

Well connected: Ten per cent of individual differences in intelligence could be explained by the strength of neural pathways connecting the left lateral prefrontal cortex

Well connected: Ten per cent of intelligence could be explained by the strength of neural pathways connecting the left lateral prefrontal cortex

'Our research shows that connectivity with a particular part of the prefrontal cortex can predict how intelligent someone is,' said Michael Cole, PhD, a postdoctoral research fellow in cognitive neuroscience at Washington University and lead author of the study.

He says the research is the first to provide compelling evidence that neural connections between the lateral prefrontal cortex and the rest of the brain make a unique and powerful contribution to the cognitive processing underlying human intelligence.

'This study suggests that part of what it means to be intelligent is having a lateral prefrontal cortex that does its job well; and part of what that means is that it can effectively communicate with the rest of the brain,' added study co-author Todd Braver, PhD, professor of psychology in Arts & Sciences and of neuroscience and radiology in the School of Medicine.

One possible explanation of the findings, the research team suggests, is that the lateral prefrontal region is a 'flexible hub' that uses its connectivity to monitor and influence other brain regions.

'There is evidence that the lateral prefrontal cortex is the brain region that "remembers" the goals and instructions that help you keep doing what is needed when you're working on a task,' said Prof Cole.

'So it makes sense that having this region communicating effectively with other regions (the "perceivers" and "doers" of the brain) would help you to accomplish tasks intelligently.'

While other regions of the brain make their own special contribution to cognitive processing, it is the lateral prefrontal cortex that helps coordinate these processes and maintain focus on the task at hand. This happens in much the same way that the conductor of a symphony monitors and tweaks the real-time performance of an orchestra.

'We're suggesting that the lateral prefrontal cortex functions like a feedback control system that is used often in engineering, that it helps implement cognitive control (which supports fluid intelligence), and that it doesn't do this alone,' said Prof Cole.

Brain scans: The findings are based on an analysis of functional magnetic resonance (fMRI) brain images

Brain scans: The findings are based on an analysis of functional magnetic resonance (fMRI) brain images

The findings are based on an analysis of functional magnetic resonance (fMRI) brain images captured as study participants rested passively and also when they were engaged in a series of mentally challenging tasks associated with fluid intelligence, such as indicating whether a currently displayed image was the same as one displayed three images ago.

Previous findings relating lateral prefrontal cortex activity to challenging task performance were supported. Connectivity was then assessed while participants rested, and their performance on additional tests of fluid intelligence and cognitive control collected outside the brain scanner was associated with the estimated connectivity.

Results indicate that levels of global brain connectivity with a part of the left lateral prefrontal cortex serve as a strong predictor of both fluid intelligence and cognitive control abilities.

Although much remains to be learned about how these neural connections contribute to fluid intelligence, new models of brain function suggested by this research could have important implications for the future understanding — and perhaps augmentation — of human intelligence.

The findings also may offer new avenues for understanding how breakdowns in global brain connectivity contribute to the profound cognitive control deficits seen in schizophrenia and other mental illnesses, Prof Cole suggests.

It ISN'T 'who you know': Coming from a well-connected family helps get a job - but success is down to your own brain power
  • Connections mean a higher first wage - but brain power soon overtakes
  • Over time, intelligence is factor that dictates earnings and success
  • Coming from a wealthy background has little impact on lifetime earnings

Being able to call on the 'old boy's network' helps you get your 'foot in the door' - but has no impact on your success.

Having 'good connections' DO change your likelihood of being offered a high wage when you start - but have no impact on your eventual wage.

The provocative study is sure to infuriate those angered by wealthy groups such as Oxford's upper-crust Bullingdon Club, of which both David Cameron and Boris Johnson were members.

Oxford's Bullingdon Club today: The provocative study is sure to infuriate those angered by societies such as Oxford's upper-crust Bullingdon Club, of which both David Cameron and Boris Johnson were members

Oxford's Bullingdon Club today: The provocative study is sure to infuriate those angered by societies such as Oxford's upper-crust Bullingdon Club, of which both David Cameron and Boris Johnson were members

The speed of your 'rise through the ranks' is dictated largely by your own intelligence.

The study, of 2,868 Americans from 1979 through 2004, monitored earnings and promotions over the course of 25 years.

Scores were used to assess the 'socio-economic background' - wealth and connections - and standard Army intelligence tests used to assess intelligence.

Profesor Yoav Ganzach of the University of Tel Aviv says that these findings, published in the journal Intelligence, have a positive message for those who can’t rely on nepotism for their first job placements.

‘Your family can help you launch your career and you do get an advantage, but it doesn’t help you progress. And once you start working, you can go wherever your abilities take you,’ he says.

When intelligence and socio-economic background (SEB) are pitted directly against one another, intelligence is a more accurate predictor of future career success, he asserts.

Eton Schoolboys in uniform: Many of Britain's top politicians attended the schoool

Eton Schoolboys in uniform: Many of Britain's top politicians attended the schoool

Taking into account each participant’s rate of advancement throughout the career arc, the data confirmed that while both intelligence and SEB impacted entry-level wages, only intelligence had an influence on the pace of pay increases throughout the years.

When looking at rates of advancement, intelligence won out over SEB in terms of career advancement.

How Rain Man's brain REALLY worked: New scans reveal the makeup of patients with similar condition
  • Researchers use brain scans and network analysis to map the brains of patients with agenesis of the corpus callosum

  • People with this condition, which affected real-life Rain Man Kim Peek, are lacking the neurological structure which connects the left and right brains

  • Scientists hope their findings will shed light on why some people with the condition develop autism and others do not

New research using brain scans sheds light on the way that the Rain Man's remarkable brain worked. Scientists at UC San Francisco and UC Berkeley combined hospital MRIs with a mathematical tool called network analysis to make 3D maps of the brains of seven adults who have the same condition. These 'structural connectome' maps, described in the upcoming April 15 issue of the journal Neuroimage, reveal new details about the condition known as agenesis of the corpus callosum.

Megasavant: Tom Cruise, left, and Dustin Hoffman, right, in a frame from the Hollywood film Rain Man, which was based on Kim Peek, a famous sufferer of agenesis of the corpus callosum

Immortalised on the silver screen: Tom Cruise, left, and Dustin Hoffman, right, in a frame from the Hollywood film Rain Man, which was based on Kim Peek, a famous sufferer of agenesis of the corpus callosum

This is where genetic malformations leave patients without a corpus callosum, the neurological structure that connects the left and right sides of the brain.

That condition is one of the top genetic causes of autism and was part of the mysterious brain physiology of Laurence Kim Peek, the remarkable savant portrayed by Dustin Hoffman in the 1987 movie Rain Man.

Mr Peek, from Utah, who died in 2009 aged 58, was known as a 'megasavant' for his exceptional memory, but he also experienced significant social difficulties. He could speed through a book in about an hour and remember almost everything he had read, memorising vast amounts of information in subjects ranging from history and literature, geography and numbers to sports, music and dates.

But while his amazing memory emerged as early as 16 months, he could not walk until the age of four, could not button up his own shirts and scored a below-average 87 on general IQ tests.

While some people born with agenesis of the corpus callosum are of normal intelligence and do not have any obvious signs of neurologic disease, approximately 40 per cent of people with the condition are at high risk for autism.

Megasavant: Kim Peek, who in 2009, could speed through a book in about an hour and remember almost everything he had read but could not button up his own shirts and scored a below-average 87 on general IQ tests

Megasavant: Kim Peek, who in 2009, could speed through a book in about an hour and remember almost everything he had read but could not button up his own shirts and scored a below-average 87 on general IQ tests

Given this, the work is a step toward finding better ways to image the brains of people with the condition, said Dr Pratik Mukherjee, a professor of radiology and biomedical imaging at UCSF.

Understanding how brain connectivity varies from person to person may help researchers identify imaging biomarkers for autism to help diagnose it and manage care for individuals.

Currently autism is diagnosed and assessed based on cognitive tests, such as those involving stacking blocks and looking at pictures on flip cards.

While the new work falls short of a quantitative measure doctors could use instead of cognitive testing, it does offer a proof-of-principle that this novel technique may shed light on neurodevelopment disorders.

'Because you are looking at the whole brain at the network level, you can do new types of analysis to find what's abnormal,' Dr Mukherjee said.

Different brain structures: Example midline sagittal and coronal colour fractional anisotropy (FA) images for a control subject with a normal brain and a patient suffering from agenesis of the corpus callosum

Different brain structures: Example midline sagittal and coronal colour fractional anisotropy (FA) images for a control subject with a normal brain and a patient suffering from agenesis of the corpus callosum

Agenesis of the corpus callosum can arise if individuals are born missing DNA from chromosome 16 and often leads to autism.

Scientists have long puzzled over what the link is between this disorder and the autistic brain,  especially since not all people with this malformation develop autism, said Dr Elliott Sherr, professor of neurology and genetics.

Doctors believe this is because the brain has a rich capacity for rewiring in alternative ways.

Pursuing this question, Dr Mukherjee and Dr Sherr turned to MRI and the mathematical technique of network analysis, which has previously been used by urban planners to optimise the timing of traffic lights to speed traffic.

The researchers believe their study is the first to apply network analysis to brain mapping for a genetic cause of autism.

Network analysis: These structural connectome maps show the differences in brain wiring between three subjects with agenesis of the corpus callosum and three subjects with normal brains

Network analysis: These structural connectome maps show the differences in brain wiring between three subjects with agenesis of the corpus callosum and three subjects with normal brains

The brain offers a significantly complicated challenge for analysis because, unlike the streets of a given city, the brain has hundreds of billions of neurons.

Many of these make tens of thousands of connections to each other, making its level of connectivity highly complex.

By comparing the seven rain man-like brains to those of 11 people without this malformation, the scientists determined how particular structures called the cingulate bundles were smaller and the neurons within these bundles were less connected to others in the brain.

They also found that the network topology of the brain was more variable in people with agenesis of the corpus callosum than in people without the malformation.

Dr Mukherjee and Dr Sherr are senior authors on the study, which is already available online.

  • The Human Connectome Project released high quality images of the brain

  • They say it will have a 'major impact' on our understanding of the organ

  • The project aims to make advanced brain images freely available

Scientists have released high quality images of the brain that they claim will have a ‘major impact’ on our understanding of the organ. Following a five year project involving more than 100 researchers from ten institutions, the experts have released the data that they hope will enable the exploration of the relationships between brain circuits and an individual's behaviour. The Human Connectome Project, which involves scientists across Europe and the USA, aims to collect data using advanced brain imaging methods, and to make the data freely available so that scientists worldwide can make further discoveries about brain circuitry.

A map of average 'functional connectivity' in human cerebral cortex

A map of average 'functional connectivity' in human cerebral cortex

An MRI scan of the brain at rest

An MRI scan of the brain at rest

The initial data release includes brain imaging scans plus behavioural information — individual differences in personality, cognitive capabilities, emotional characteristics and perceptual function — obtained from 68 healthy adult volunteers. It is particularly notable because the new data has much higher resolution in space and time than data obtained by conventional brain scans.Over the next few years the number of people studied will increase until the researchers reach their final target of 1,200. The Human Connectome Project consortium is led by Dr David Van Essen, Alumni Endowed Professor at Washington University School of Medicine in St. Louis.

One of the 'connection maps' created by the team, which shows pathways in the brain of volunteers

One of the 'connection maps' created by the team, which shows pathways in the brain of volunteers

The project will publish all of its data online and make it accessible for researchers

The project will publish all of its data online and make it accessible for researchers

He said: ‘By making this unique data set available now, and continuing with regular data releases every  quarter, the Human Connectome Project is enabling the scientific community to immediately begin exploring relationships between brain circuits and individual behaviour. ‘The HCP will have a major impact on our understanding of the healthy adult human brain, and it will set the stage for future projects that examine changes in brain circuits underlying the wide variety of brain disorders afflicting humankind.’

A composite of the scans of 20 individuals. Regions in yellow and red are linked to the parietal lobe of the brain's right hemisphere

A composite of the scans of 20 individuals. Regions in yellow and red are linked to the parietal lobe of the brain's right hemisphere

Yellow and red regions are activated by a task involving listening to stories, whereas green and blue regions are more strongly activated by a task involving arithmetic calculations

Yellow and red regions are activated by a task involving listening to stories, whereas green and blue regions are more strongly activated by a task involving arithmetic calculations

The data set includes information about brain connectivity in each individual, using two distinct magnetic resonance imaging (MRI) approaches.

One is based on spontaneous fluctuations in functional MRI signals that occur in a complex pattern in space and time throughout the gray matter of the brain.

Another, called diffusion imaging, provides information about the long-distance ‘wiring’ – the anatomical pathways traversing the brain’s white matter.

Brain activations in the brain's grey matter. Yellow and red regions are activated when subjects view human faces

Brain activations in the brain's grey matter. Yellow and red regions are activated when subjects view human faces

Each subject was also scanned while performing a variety of tasks within the scanner, thereby providing extensive information about brain activation patterns.

Behavioural data using a variety of tests performed outside the scanner are being released along with the scan data for each subject.

The subjects are drawn from families that include siblings, some of whom are twins. This will enable studies of the heritability of brain circuits.

Dr Daniel Marcus, assistant professor of radiology and director of the Neuroinformatics Research Group at Washington University School of Medicine, said: ‘The Human Connectome Project represents a major advance in sharing brain imaging data in ways that will accelerate the pace of discovery about the human brain in health and disease.’

Some people will never learn – and now scientists think they know why. People who keep repeating the same mistakes have less active brains. The study at Goldsmiths, University of London, is one of the first to try and work out why some people are better at learning from their mistakes than others.

The team studied whether participants were able to listen to feedback and improve their performance on a series of tests.

The researchers analysed eletrical brain responses, and identified some people, called high learners, and shown on the left, could learn from mistakes better than others, dubbed low learners

The researchers analysed electrical brain responses, and identified some people, called high learners, and shown on the left, could learn from mistakes better than others, dubbed low learners

They found that the results varied significantly.

The research, led by Professor Joydeep Bhattacharya in the Department of Psychology at Goldsmiths, examined what it is about the brain that defines someone as a 'good learner' from those who do not learn from their mistakes.

'We are always told how important it is to learn from our errors, our experiences, but is this true?,' he said.

'If so, then why do we all not learn from our experiences in the same way? It seems some people rarely do, even when they were informed of their errors in repeated attempts. 'This study presents a first tantalising insight into how our brain processes the performance feedback and what it does with this information, whether to learn from it or to brush it aside.'

The study, published in a recent issue of the Journal of Neuroscience, investigated brainwave patterns of 36 healthy human volunteers performing a simple time estimation task.

Researchers asked the participants to estimate a time interval of 1.7 seconds and provided feedback on their errors.

The participants were then measured to see whether they incorporated the feedback to improve their future performances.

'Good learners', who were successful in incorporating the feedback information in adjusting their future performance, presented increased brain responses as fast as 200 milliseconds after the feedback on their performance was presented on a computer screen.

Researchers say that different people learn in very different ways - with 'high learners' far better at learning from their mistakes

Researchers say that different people learn in very different ways - with 'high learners' far better at learning from their mistakes

This brain response was weaker in the poor learners who did not learn the task well and who showed decreased responses to their performance errors.

The researchers further found that the good learners showed increased communication between brain areas involved with performance monitoring and some motor processes.

Caroline Di Bernardi Luft, one of the research paper's co-authors from the Federal University of Santa Catarina, commented: 'Good learners used the feedback not only to check their past performance, but also to adjust their next performance accordingly.' The brain responses correlated highly with how well the volunteers learned this simple task over the course of the experiment, and how good they were at maintaining the learned skill without any guiding feedback.Babies born up to three months premature can recognise different syllables in human speech, say scientists.

A study showed similarities in the way the brain processes language in the new-borns and adults - including specific neurological reactions to changes from the 'ba' to 'ga' sound and to a male to female voices.

Professor Fabrice Wallois, of Picardie University in Amiens, France, said the findings suggest that early in the development of the brain it begins to decipher distinct sounds or 'phonemes'.

The study showed similarities in the way the brain processes language in the new-borns and adults - including specific neurological reactions to changes from the

The study showed similarities in the way the brain processes language in the new-borns and adults - including specific neurological reactions to changes from the "ba" to "ga" sound and to a male to female voices.

HOW THEY DID IT

Using bedside functional optical imaging, Fabrice Wallois and colleagues scanned 12 sleeping 28-32-week gestation age pre-term infants.

This is the earliest age at which cortical responses to external stimuli can be recorded. He said as early as three months before birth a baby's brain establishes neural functions that help decipher human speech. At birth children can discriminate some syllables and recognise human speech but how these immature brain cells process it remains unclear.Using powerful non-invasive scanners Prof Wallois and colleagues analysed 12 sleeping premature infants born after 28 to 32 weeks while playing voice recordings. This is the earliest age for neuronal responses to external stimuli and Prof Wallois found the premature brain can perceive differences in syllables. In addition although the tests produced responses in the right frontal region of the brain - the first part of the brain to form - syllabic changes also sparked responses in the left hemisphere. This suggests certain linguistic brain areas exhibit a sophisticated degree of organisation as early as three months prior to full term.

Prof Wallois said: 'We observed several points of similarity with the adult linguistic network.

The research gives a new insight into the way mothers communicate with their babies - and how language skills develop

The research gives a new insight into the way mothers communicate with their babies - and how language skills develop. 'First, whereas syllables elicited larger right than left responses, the posterior temporal region escaped this general pattern, showing faster and more sustained responses over the left than over the right hemisphere. 'Second, discrimination responses to a change of phoneme (ba vs. ga) and a change of human voice (male vs. female) were already present and involved inferior frontal areas, even in the youngest infants. 'Third, whereas both types of changes elicited responses in the right frontal region, the left frontal region only reacted to a change of phoneme.'These results demonstrate a sophisticated organisation of areas at the very onset of cortical circuitry - three months before term. 'They emphasise the influence of innate factors on regions involved in linguistic processing and social communication in humans.'The study is published in Proceedings of the National Academy of Sciences.

Thank your parents if you're smart: Up to 40% of a child's intelligence is inherited, researchers claim

New estimate is lower than those given by previous studies. Researchers analysed DNA and IQ test results from 18,000 children. They suggest a range of genes may affect intelligence cumulatively

It's all in the genes: A new study shows that up to 40 per cent of a child's intelligence is passed down from the parents

It's all in the genes: A new study shows that up to 40 per cent of a child's intelligence is passed down from the parents. Up to 40 per cent of a child's intelligence is passed down from the parents, according to a new study. The finding from the largest ever genetic study of childhood intelligence adds yet more fuel to the debate over whether intelligence is a product of nature or nurture. Using genetic data and IQ scores of thousands of children from four countries, researchers from the University of Queensland found attempted to separate out the environmental effects. They found that between 20 and 40 per cent of the variation in childhood IQ is due to genetic factors, less than the 40 to 50 per cent suggested by previous research. Dr Beben Benyamin, from the University of Queensland, told ABC: 'This estimate from DNA information is lower than family studies, but it is consistent with the conclusion childhood intelligence is heritable.' Dr Benyamin and his colleagues analysed DNA samples from 18,000 children aged six to 18 from Australia, the Netherlands, the UK and the U.S, along with their IQ scores.

They looked for any correlations between patterns of differences in the youngsters' DNA with patterns of differences in their IQ. Findings showed that a gene known as FNBP1L was significantly linked to childhood intelligence. The same gene had previously been shown to be the most significant gene in predicting adult intelligence. Usually when looking at how genetic factors influence individual traits scientists prefer to look for gene variants known as single-nucleotide polymorphisms (SNPs), as these give more precise genetic information, ABC reported. However, Professor Benyamin said, the study did not find any single SNP gene variant that could strongly predict childhood intelligence.

Nature or nurture? It could be many genes that contribute to intelligence in children, with each having a small, but cumulative effect, the study suggests

Nature or nurture? It could be many genes that contribute to intelligence in children, with each having a small, but cumulative effect, the study suggests. 'But when we looked at the combined effect of all SNPs we can estimate the contribution of genetics to be about 20 to 40 per cent of the difference in IQ,' he said. That means it could be many genes that contribute to intelligence in children, with each having a small, but cumulative effect, the study suggests. Understanding the factors influencing intelligence is important since IQ is a good predictor for lifespan, educational achievement and adult income, said Professor Benyamin. The findings may also help researchers to better understand intellectual disability, he added.

 

 

Time travel could create doppelgangers that would destroy each other

 

 

 

 

 

 

Fireworks far, far away: This new composite image of NGC 4258, where X-rays from NASA's Chandra X-ray Observatory are blue, radio data from the NSF's Karl Jansky Very Large Array are purple, optical data from NASA's Hubble Space Telescope are yellow and blue, and infrared data from NASA's Spitzer Space Telescope are red.

Fireworks far, far away: This new composite image of NGC 4258, where X-rays from NASA's Chandra X-ray Observatory are blue, radio data from the NSF's Karl Jansky Very Large Array are purple, optical data from NASA's Hubble Space Telescope are yellow and blue, and infrared data from NASA's Spitzer Space Telescope are red.

 

Wormholes are theoretical tunnels that create shortcuts in space-time. A study in May from Dr Luke Butcher at Cambridge University argued that if a thin wormhole stayed open long enough, people could send messages through time using pulses of light, or photonsResearchers at the University of Queensland in Australia have discovered that two photons travelling through time can interact. In the simulation a photon stuck in a closed timelike curve (illustrated) through a wormhole was found to be capable of interacting with one travelling through regular space-time    
 

Could time travel soon become a reality? Physicists simulate sending quantum light particles into the past

  • University of Queensland scientists simulate photons moving through time
  • They showed how two wormhole-travelling photons might behave
  • Time-travel in the quantum world seems to avoid famous paradoxes
  • The experiment shows bizarre behaviour of such quantum particles
  • But on larger scales time travel still remains implausible, say researchers

 

Back to the future? Time travel could create doppelgangers that would ultimately destroy each other, claims radical theory

  • Thought experiment done by physicist, Professor Robert Nemiroff
  • Theory based on assumption that faster-than-light travel is possible
  • Any object that goes faster-than-light is believed to travel back in time
  • If this happens, a pair of twin travellers would come into existence
  • One would have a negative mass and another twin, a positive mass
  • As a result, when they meet, they would self-destruct, theory says

Imagine a future in which you could travel backwards in time to meet your ancestors.

Only, there are some serious side effects.

The act of time-travelling would create several versions of you, some living in the present, while others move to the past.

Your doppelgangers will be destined to meet up, and when they do, they will ultimately destroy each other.

It may sound like science fiction, but one theoretical physicist has worked out mathematical equations to show how this might work using our current understanding of science.

Professor Robert Nemiroff came up with equations for travelling back in time. 'The only solutions we could find involved these strange pairs of travellers popping into and out of existence,' he said. ‘One member of this pair must have a strange type of negative mass, while the other has normal positive mass'

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Professor Robert Nemiroff came up with equations for travelling back in time. 'The only solutions we could find involved these strange pairs of travellers popping into and out of existence,' he said. 'One member of this pair must have a strange type of negative mass, while the other has normal positive mass'

WHAT WOULD HAPPEN IF YOU TRAVEL BACK IN TIME?

Travelling back in time is based on the assumption that faster-than-light travel is possible.

If this ever happened, there is no reason that the arrow of time can't be turned backwards, for objects and people to enter a so-called 'closed time-like curve'.

Mathematical equations, however, have shown that a number of strange results emerge.

In the latest study, a strange pair of objects come into and out of existence, according to the mathematical models

If you assume that one has a negative mass and one has a positive mass, the one with the negative mass will also move back in time.

It will be destined to meet up with its twin, and together, they would disappear. Professor Nemiroff describes this as an extension of something known as the 'twin paradox.'

'I had heard many times that faster-than-light motion result in backwards time travel,' Robert Nemiroff, a physicist at Michigan Technological University told DailyMail.com

'Even though I am a professional astrophysicist, I didn't understand the details of how this might work.

'So a student and I tried to work out for ourselves a very simple example.'

The example involved a spaceship that would start on a launching pad on Earth, travel at five times the speed of light to a planet about 10 light-years away.

It would then turn around to return home to a landing pad not far from the lift-off site, according to a report in LiveScience.

'It is well known - and not controversial - that you can time travel to the future by just travelling quickly in a spaceship and coming back,' said Professor Nemiroff.

'The closer one goes to the speed of light, and the longer the trip, the further into the future you can go.

'But what about the past? Can you get to the past simply by just travelling in a spaceship?'

The only way this could happen was to assume that the spaceship could travel faster than the speed of light, and return.

'Although in retrospect the equations were simple, it took us quite some effort to figure out how this might work,' said Professor Nemiroff.

'Even so, the only solutions we could find involved these strange pairs of travellers popping into and out of existence.

'We speculated that one member of this pair must have a strange type of negative mass, while the other has normal positive mass.'

Using Professor Nemiroff's equations, it turned out that a pair of ghost-ships, one with negative mass and one with positive mass, would appear out of thin air.

In the latest thought experiment, a spaceship would start on a launching pad on Earth, travel at five times the speed of light to a planet about 10 light-years away. Because the light from the spaceship travels slower than the spaceship, after it returns, Earthlings would see images of the spaceship on its way out

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In the latest thought experiment, a spaceship would start on a launching pad on Earth, travel at five times the speed of light to a planet about 10 light-years away. Because the light from the spaceship travels slower than the spaceship, after it returns, Earthlings would see images of the spaceship on its way out

Because the light from the spaceship travels slower than the spaceship, after it returns, Earthlings would see images of the spaceship on its way out, and another on its way back.

Eight years later, an image of the spaceship sitting on the launch pad will still be visible, as would two images of the spaceship on its outbound and return flights.

After about 10 years, the phantom spaceship pairs would destroy each other and there would only one spaceship sitting on the landing pad.

The same thing would happen with any object travelling back in time.

'For example, if in Doctor Who, two Doctors were standing right next to each other, we found that a third Doctor must exist, of negative mass, hurtling away faster than light,' explained Professor Nemiroff.

'This third Doctor is destined to meet up with one of the original Doctors and, together, disappear. This superluminal Doctor would also appear to be moving time-backwards.'

The thought experiment creates more questions than it answers. For instance, what would the doppelgangers be made of? And which would be the 'real one'?

The physicist says he doesn't have the answers, but in any case, he doesn't think this would ever be a reality.

'Unfortunately, it does not seem possible for physical things to travel faster than light, and that is a crucial step,' he said.

'We can make shadows and light spots from laser pointers appear to move that fast, but no one has ever been able to make something physical - with mass - move that fast.

'So time travel to the past seems impossible, at least presently.'

Professor Nemiroff's equations are described in a paper published in May in the preprint journal

 

 

If a time traveller went back in time and stopped their own grandparents from meeting, would they prevent their own birth?

That’s the crux of an infamous theory known as the 'grandfather paradox', which is often said to mean time travel is impossible - but some researchers think otherwise.

A group of scientists have simulated how time-travelling photons might behave, suggesting that, at the quantum level, the grandfather paradox could be resolved

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Researchers at the University of Queensland in Australia have discovered that two photons travelling through time can interact. In the simulation a photon stuck in a closed timelike curve (illustrated) through a wormhole was found to be capable of interacting with one travelling through regular space-time

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Researchers at the University of Queensland in Australia have discovered that two photons travelling through time can interact. In the simulation a photon stuck in a closed timelike curve (illustrated) through a wormhole was found to be capable of interacting with one travelling through regular space-time

 

The research was carried out by a team of researchers at the University of Queensland in Australia and their results are published in the journal Nature Communications.

WHAT IS A WORMHOLE?

Space-time can be warped and distorted. It takes an enormous amount of matter or energy to create such distortions, but theoretically, distortions are possible.

In the case of a wormhole, a shortcut is made by warping the fabric of space-time. Imagine folding a piece of paper with two pencil marks drawn on it to represent two points in space-time.

The line between them shows the distance from one point to the other in normal space-time.

If the paper is now bent and folded over almost double - the equivalent to warping space-time -  then poking the pencil through the paper provides a much shorter way of linking the two points, in the same way a wormhole would create a shortcut.

The problem with using wormholes to travel in space or time is that they are inherently unstable.  When a particle enters a wormhole, it also creates fluctuations that cause the structure to collapse in on it.

A recent study suggests there are unusual-shaped wormholes than may be able to stay open longer than normal.

The study used photons - single particles of light - to simulate quantum particles travelling back through time.

By studying their behaviour, the scientists revealed possible bizarre aspects of modern physics. In the simulation, the researchers examined two possible outcomes for a time-travelling photon.

In the simulation, the researchers examined the behaviour of a photon traveling through time and interacting with its older self.

In their experiment they made use of the closely related, fictitious, case where the photon travels through normal space-time and interacts with another photon that is stuck in a time-travelling loop through a wormhole, known as a closed timelike curve (CTC).

Simulating the behaviour of this second photon, they were able to study the behaviour of the first - and the results show that consistent evolutions can be achieved when preparing the second photon in just the right way.

By definition ‘quantum’ refers to the smallest possible particles that can independently exist - such as photons.

However, for macroscopic systems time-travel still faces problematic paradoxes.

In 1991 it was first predicted that time travel would be possible in the ‘quantum world’ because quantum particles behave almost outside the realms of physics.

Wormholes are theoretical tunnels that create shortcuts in space-time. A study in May from Dr Luke Butcher at Cambridge University argued that if a thin wormhole stayed open long enough, people could send messages through time using pulses of light, or photons

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Wormholes are theoretical tunnels that create shortcuts in space-time. A study in May from Dr Luke Butcher at Cambridge University argued that if a thin wormhole stayed open long enough, people could send messages through time using pulses of light, or photons

'The properties of quantum particles are "fuzzy" or uncertain to start with, so this gives them enough wiggle room to avoid inconsistent time travel situations,' said professor Timothy Ralph, one of the researchers on the latest study.

The results also give a better understand to how two theories in physics, on the biggest and smallest scales, are able to relate to one another.

'The question of time travel features at the interface between two of our most successful yet incompatible physical theories ' Einstein's general relativity and quantum mechanics,' said PhD student Martin Ringbauer from the University of Queensland.

'Einstein's theory describes the world at the very large scale of stars and galaxies, while quantum mechanics is an excellent description of the world at the very small scale of atoms and molecules.'

Einstein's theory suggests the possibility of travelling backwards in time by following a space-time path that returns to the starting point in space but at an earlier time - a closed timelike curve (CTC).

This possibility has puzzled physicists and philosophers alike since it was discovered by Austrian-American scientist Kurt Gödel in 1949, as it seems to cause paradoxes in the classical world.

These include the 'grandparents paradox', where a time traveller could stop their grandparents from meeting, thus preventing the time traveller's birth.

This would make it impossible for the time traveller to have set out in the first place.

But this new research suggests that such interactions might indeed be possible - albeit only on a quantum level.

 

 

 

 

 
Scientists prove nothing can travel faster than the speed of light. For those that while away their days dreaming about travelling into the distant past or future, it is disappointing news.

But scientists claim to have proved that a single photon obeys Einstein's theory that nothing can travel faster than the speed of light - meaning time travel is impossible.

Their findings close a decade-long debate about the speed of a single photon, the fundamental unit of light.

Scientists have proved that a single photon obeys Einstein's theory that nothing can travel faster than the speed of light

No heading Back To The Future: Scientists have proved that a single photon obeys Einstein's theory that nothing can travel faster than the speed of light and that time travel is therefore impossible

Lead researcher Professor Shengwang Du, from the Hong Kong University of Science and Technology (HKUST), said: 'The results add to our understanding of how a single photon moves. They also confirm the upper bound on how fast information travels with light.

'By showing that single photons cannot travel faster than the speed of light, our results bring a closure to the debate on the true speed of information carried by a single photon.'

Professor Du and his team found that a single photon obeys the traffic law of the universe.

Einstein claimed that the speed of light was the traffic law of the universe - or, simply, that nothing can travel faster than light.

The HKUST team is the first to show that optical precursors exist at the single-photon level, and that they are the fastest part of the single-photon wave packet even in a so-called 'superluminal' - or faster than light - medium.

Mankind's long-held dream of time travel was given a shot in the arm ten years ago with the discovery of superluminal propagation of optical pulses in some specific medium.

But scientists later realised that it is only a visual effect - where the superluminal 'group' velocity of many photons could not be used for transmitting any real information.

Hard at work: Lead researcher Shengwang Du and his team measured the ultimate speed of a single photon with controllable waveforms

Hard at work: Lead researcher Shengwang Du and his team measured the ultimate speed of a single photon with controllable waveforms

Researchers then set their hope on single photons because of the possibility that a single photon may be able to travel faster.

Due to a lack of evidence of single photon velocity, this has also been an open debate among physicists.

To confront this impasse, Professor Du's team measured the ultimate speed of a single photon with controllable waveforms.

Their study confirmed Einstein's theory that an effect cannot occur before its cause.

The researchers not only produced single protons but separated the optical precursor - the wave-like propagation at the front of an optical pulse - from the rest of the photon wave packet.

To do so, they generated a pair of photons, and then passed one of them through a group of laser-cooled rubidium atoms with an effect called electromagnetically induced transparency.

For the first time, they successfully observed optical precursors of a single photon.

The team found that, as the fastest part of a single photon, the precursor wave front always travels at the speed of light in vacuum.

The main wave packet of the single photon travels no faster than the speed of light in vacuum in any dispersive medium, and can be delayed up to 500 nanoseconds in a slow light medium.

Even in a superluminal medium where the group velocity is faster than the speed of light in vacuum, the main part of the single photon has no possibility to travel faster than its precursor

Stephen Hawking: "Time Travel to the Future is Possible"

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"I do believe in time travel. Time travel to the future. Time flows like a river and it seems as if each of us is carried relentlessly along by time's current. But time is like a river in another way. It flows at different speeds in different places and that is the key to travelling into the future. This idea was first proposed by Albert Einstein over 100 years ago."

Stephen Hawking

Needed for assembly: "One wormhole, the Large Hadron Collider, or a rocket that goes really, really fast."

Stephen Hawking thinks for of the world's physicists are wrong believing that time travel is impossible: Hawking sides with Sir Arthur Clarke, author of Space Odyssey 2001 who famously stated that "when a distinguished scientist states that something is impossible, he is very probably wrong".  And a lot of distinguished scientists believe that just "Time travel is absolutely impossible".

Hawking says: "Although I cannot move and I have to speak through a computer, in my mind I am free. Free to explore the universe and ask the big questions, such as: is time travel possible? Can we open a portal to the past or find a shortcut to the future? Can we ultimately use the laws of nature to become masters of time itself?"
Several of the planet's leading scientists, including Charles Liu (author of "One Universe: At Home In The Cosmos"), Brian Greene (of "The Elegant Universe") and Michio Kaku ("Hyperspace") float a raft of objections to the concept of time travel. True to Clarke's statement, sometimes affectionately known as "Clarke's Law", each objection seems more like reason to expect time travel than rule it out.

Professor Greene states that all time-travel theories operate at the very boundaries of known physics, and are therefore unlikely to work.  As opposed to, say, the boundaries of our understanding being where new discoveries are made.  As Sir Clarke said years ago: "The only way of discovering the limits of the possible is to venture a little way past them into the impossible".

3879394733_92091d29b0The other chief objection is the incomprehensible amounts of energy required to punch a hole in spacetime, or stabilize a wormhole, or engineer a double-cosmic-string-ring (yes, that's a real astrophysical concept) capable of bending space hard enough to let us pop back to the past.  One point eighty-one jigawatts just isn't going to cut it here, whatever "jigawatts" turn out to be, and most calculations show that powering a time machine with a lightning strike would be like powering a sixteen-wheeler with a bag of jelly babies.  (So it seems Marty won't be getting back to the future after all).  Of course, the idea of lighting up New York would have had you committed to a mental home in the early eighteenth century.  Pre-electricity, schemes were being suggested to transport the increasing numbers of people to the scant available heat and light in times of need.
Understand: the amount of energy we now take for granted was so vast, so utterly unimaginable to people in the past that they were preparing to restructure their whole society rather than even attempt to generate it.  Of course, this doesn't guarantee that we'll be able to pop back and tell them.  The false argument of past scientific ignorance, the "didn't scientists used to think the world was flat" gambit fails because we know so much more now.  The key to progress is our cumulative knowledge, developed and refined by generations of researchers into a vast, accurate body of knowledge.  We are far more likely to be able to find what's possible than at any point in history.  What we know so far is probably right, and allows us to make predictions about what might be possible.
But until we can explain absolutely everything, we should still steer clear of saying something is impossible. Here's what our beloved Professor Hawking says about time travel in his post in The Daily Mail:

"Time travel was once considered scientific heresy. I used to avoid talking about it for fear of being labeled a crank. But these days I'm not so cautious. In fact, I'm more like the people who built Stonehenge. I'm obsessed by time. If I had a time machine I'd visit Marilyn Monroe in her prime or drop in on Galileo as he turned his telescope to the heavens. Perhaps I'd even travel to the end of the universe to find out how our whole cosmic story ends.

"To see how this might be possible, we need to look at time as physicists do - at the fourth dimension. It's not as hard as it sounds. Every attentive schoolchild knows that all physical objects, even me in my chair, exist in three dimensions. Everything has a width and a height and a length.

"But there is another kind of length, a length in time. While a human may survive for 80 years, the stones at Stonehenge, for instance, have stood around for thousands of years. And the solar system will last for billions of years. Everything has a length in time as well as space. Travelling in time means travelling through this fourth dimension.

"To see what that means, let's imagine we're doing a bit of normal, everyday car travel. Drive in a straight line and you're travelling in one dimension. Turn right or left and you add the second dimension. Drive up or down a twisty mountain road and that adds height, so that's travelling in all three dimensions. But how on Earth do we travel in time? How do we find a path through the fourth dimension?

"Let's indulge in a little science fiction for a moment. Time travel movies often feature a vast, energy-hungry machine. The machine creates a path through the fourth dimension, a tunnel through time. A time traveller, a brave, perhaps foolhardy individual, prepared for who knows what, steps into the time tunnel and emerges who knows when. The concept may be far-fetched, and the reality may be very different from this, but the idea itself is not so crazy.

"Physicists have been thinking about tunnels in time too, but we come at it from a different angle. We wonder if portals to the past or the future could ever be possible within the laws of nature. As it turns out, we think they are. What's more, we've even given them a name: wormholes. The truth is that wormholes are all around us, only they're too small to see. Wormholes are very tiny. They occur in nooks and crannies in space and time. You might find it a tough concept, but stay with me.

"A wormhole is a theoretical 'tunnel' or shortcut, predicted by Einstein's theory of relativity, that links two places in space-time - visualised above as the contours of a 3-D map, where negative energy pulls space and time into the mouth of a tunnel, emerging in another universe. They remain only hypothetical, as obviously nobody has ever seen one, but have been used in films as conduits for time travel - in Stargate (1994), for example, involving gated tunnels between universes, and in Time Bandits (1981), where their locations are shown on a celestial map

"Nothing is flat or solid. If you look closely enough at anything you'll find holes and wrinkles in it. It's a basic physical principle, and it even applies to time. Even something as smooth as a pool ball has tiny crevices, wrinkles and voids. Now it's easy to show that this is true in the first three dimensions. But trust me, it's also true of the fourth dimension. There are tiny crevices, wrinkles and voids in time. Down at the smallest of scales, smaller even than molecules, smaller than atoms, we get to a place called the quantum foam. This is where wormholes exist. Tiny tunnels or shortcuts through space and time constantly form, disappear, and reform within this quantum world. And they actually link two separate places and two different times.

"Unfortunately, these real-life time tunnels are just a billion-trillion-trillionths of a centimetre across. Way too small for a human to pass through - but here's where the notion of wormhole time machines is leading. Some scientists think it may be possible to capture a wormhole and enlarge it many trillions of times to make it big enough for a human or even a spaceship to enter.

"Given enough power and advanced technology, perhaps a giant wormhole could even be constructed in space. I'm not saying it can be done, but if it could be, it would be a truly remarkable device. One end could be here near Earth, and the other far, far away, near some distant planet.

"Theoretically, a time tunnel or wormhole could do even more than take us to other planets. If both ends were in the same place, and separated by time instead of distance, a ship could fly in and come out still near Earth, but in the distant past. Maybe dinosaurs would witness the ship coming in for a landing.

"The fastest manned vehicle in history was Apollo 10. It reached 25,000mph. But to travel in time we'll have to go more than 2,000 times faster

"Now, I realise that thinking in four dimensions is not easy, and that wormholes are a tricky concept to wrap your head around, but hang in there. I've thought up a simple experiment that could reveal if human time travel through a wormhole is possible now, or even in the future. I like simple experiments, and champagne.

"So I've combined two of my favourite things to see if time travel from the future to the past is possible.

"Let's imagine I'm throwing a party, a welcome reception for future time travellers. But there's a twist. I'm not letting anyone know about it until after the party has happened. I've drawn up an invitation giving the exact coordinates in time and space. I am hoping copies of it, in one form or another, will be around for many thousands of years. Maybe one day someone living in the future will find the information on the invitation and use a wormhole time machine to come back to my party, proving that time travel will, one day, be possible.

"In the meantime, my time traveller guests should be arriving any moment now. Five, four, three, two, one. But as I say this, no one has arrived. What a shame. I was hoping at least a future Miss Universe was going to step through the door. So why didn't the experiment work? One of the reasons might be because of a well-known problem with time travel to the past, the problem of what we call paradoxes.

"Paradoxes are fun to think about. The most famous one is usually called the Grandfather paradox. I have a new, simpler version I call the Mad Scientist paradox.

"I don't like the way scientists in movies are often described as mad, but in this case, it's true. This chap is determined to create a paradox, even if it costs him his life. Imagine, somehow, he's built a wormhole, a time tunnel that stretches just one minute into the past.

"Through the wormhole, the scientist can see himself as he was one minute ago. But what if our scientist uses the wormhole to shoot his earlier self? He's now dead. So who fired the shot? It's a paradox. It just doesn't make sense. It's the sort of situation that gives cosmologists nightmares.

"This kind of time machine would violate a fundamental rule that governs the entire universe - that causes happen before effects, and never the other way around. I believe things can't make themselves impossible. If they could then there'd be nothing to stop the whole universe from descending into chaos. So I think something will always happen that prevents the paradox. Somehow there must be a reason why our scientist will never find himself in a situation where he could shoot himself. And in this case, I'm sorry to say, the wormhole itself is the problem.

"In the end, I think a wormhole like this one can't exist. And the reason for that is feedback. If you've ever been to a rock gig, you'll probably recognise this screeching noise. It's feedback. What causes it is simple. Sound enters the microphone. It's transmitted along the wires, made louder by the amplifier, and comes out at the speakers. But if too much of the sound from the speakers goes back into the mic it goes around and around in a loop getting louder each time. If no one stops it, feedback can destroy the sound system.

"The same thing will happen with a wormhole, only with radiation instead of sound. As soon as the wormhole expands, natural radiation will enter it, and end up in a loop. The feedback will become so strong it destroys the wormhole. So although tiny wormholes do exist, and it may be possible to inflate one some day, it won't last long enough to be of use as a time machine. That's the real reason no one could come back in time to my party.

"Any kind of time travel to the past through wormholes or any other method is probably impossible, otherwise paradoxes would occur. So sadly, it looks like time travel to the past is never going to happen. A disappointment for dinosaur hunters and a relief for historians.

"But the story's not over yet. This doesn't make all time travel impossible. I do believe in time travel. Time travel to the future. Time flows like a river and it seems as if each of us is carried relentlessly along by time's current. But time is like a river in another way. It flows at different speeds in different places and that is the key to travelling into the future. This idea was first proposed by Albert Einstein over 100 years ago. He realised that there should be places where time slows down, and others where time speeds up. He was absolutely right. And the proof is right above our heads. Up in space.

"This is the Global Positioning System, or GPS. A network of satellites is in orbit around Earth. The satellites make satellite navigation possible. But they also reveal that time runs faster in space than it does down on Earth. Inside each spacecraft is a very precise clock. But despite being so accurate, they all gain around a third of a billionth of a second every day. The system has to correct for the drift, otherwise that tiny difference would upset the whole system, causing every GPS device on Earth to go out by about six miles a day. You can just imagine the mayhem that that would cause.

"The problem doesn't lie with the clocks. They run fast because time itself runs faster in space than it does down below. And the reason for this extraordinary effect is the mass of the Earth. Einstein realised that matter drags on time and slows it down like the slow part of a river. The heavier the object, the more it drags on time. And this startling reality is what opens the door to the possibility of time travel to the future.

"Right in the centre of the Milky Way, 26,000 light years from us, lies the heaviest object in the galaxy. It is a supermassive black hole containing the mass of four million suns crushed down into a single point by its own gravity. The closer you get to the black hole, the stronger the gravity. Get really close and not even light can escape. A black hole like this one has a dramatic effect on time, slowing it down far more than anything else in the galaxy. That makes it a natural time machine.

"I like to imagine how a spaceship might be able to take advantage of this phenomenon, by orbiting it. If a space agency were controlling the mission from Earth they'd observe that each full orbit took 16 minutes. But for the brave people on board, close to this massive object, time would be slowed down. And here the effect would be far more extreme than the gravitational pull of Earth. The crew's time would be slowed down by half. For every 16-minute orbit, they'd only experience eight minutes of time.

"Around and around they'd go, experiencing just half the time of everyone far away from the black hole. The ship and its crew would be travelling through time. Imagine they circled the black hole for five of their years. Ten years would pass elsewhere. When they got home, everyone on Earth would have aged five years more than they had.

"So a supermassive black hole is a time machine. But of course, it's not exactly practical. It has advantages over wormholes in that it doesn't provoke paradoxes. Plus it won't destroy itself in a flash of feedback. But it's pretty dangerous. It's a long way away and it doesn't even take us very far into the future. Fortunately there is another way to travel in time. And this represents our last and best hope of building a real time machine.

"You just have to travel very, very fast. Much faster even than the speed required to avoid being sucked into a black hole. This is due to another strange fact about the universe. There's a cosmic speed limit, 186,000 miles per second, also known as the speed of light. Nothing can exceed that speed. It's one of the best established principles in science. Believe it or not, travelling at near the speed of light transports you to the future.

"To explain why, let's dream up a science-fiction transportation system. Imagine a track that goes right around Earth, a track for a superfast train. We're going to use this imaginary train to get as close as possible to the speed of light and see how it becomes a time machine. On board are passengers with a one-way ticket to the future. The train begins to accelerate, faster and faster. Soon it's circling the Earth over and over again.

"To approach the speed of light means circling the Earth pretty fast. Seven times a second. But no matter how much power the train has, it can never quite reach the speed of light, since the laws of physics forbid it. Instead, let's say it gets close, just shy of that ultimate speed. Now something extraordinary happens. Time starts flowing slowly on board relative to the rest of the world, just like near the black hole, only more so. Everything on the train is in slow motion.

"This happens to protect the speed limit, and it's not hard to see why. Imagine a child running forwards up the train. Her forward speed is added to the speed of the train, so couldn't she break the speed limit simply by accident? The answer is no. The laws of nature prevent the possibility by slowing down time onboard.

"Now she can't run fast enough to break the limit. Time will always slow down just enough to protect the speed limit. And from that fact comes the possibility of travelling many years into the future.

"Imagine that the train left the station on January 1, 2050. It circles Earth over and over again for 100 years before finally coming to a halt on New Year's Day, 2150. The passengers will have only lived one week because time is slowed down that much inside the train. When they got out they'd find a very different world from the one they'd left. In one week they'd have travelled 100 years into the future. Of course, building a train that could reach such a speed is quite impossible. But we have built something very like the train at the world's largest particle accelerator at CERN in Geneva, Switzerland.

"Deep underground, in a circular tunnel 16 miles long, is a stream of trillions of tiny particles. When the power is turned on they accelerate from zero to 60,000mph in a fraction of a second. Increase the power and the particles go faster and faster, until they're whizzing around the tunnel 11,000 times a second, which is almost the speed of light. But just like the train, they never quite reach that ultimate speed. They can only get to 99.99 per cent of the limit. When that happens, they too start to travel in time. We know this because of some extremely short-lived particles, called pi-mesons. Ordinarily, they disintegrate after just 25 billionths of a second. But when they are accelerated to near-light speed they last 30 times longer.

"It really is that simple. If we want to travel into the future, we just need to go fast. Really fast. And I think the only way we're ever likely to do that is by going into space. The fastest manned vehicle in history was Apollo 10. It reached 25,000mph. But to travel in time we'll have to go more than 2,000 times faster. And to do that we'd need a much bigger ship, a truly enormous machine. The ship would have to be big enough to carry a huge amount of fuel, enough to accelerate it to nearly the speed of light. Getting to just beneath the cosmic speed limit would require six whole years at full power.

"The initial acceleration would be gentle because the ship would be so big and heavy. But gradually it would pick up speed and soon would be covering massive distances. In one week it would have reached the outer planets. After two years it would reach half-light speed and be far outside our solar system. Two years later it would be travelling at 90 per cent of the speed of light. Around 30 trillion miles away from Earth, and four years after launch, the ship would begin to travel in time. For every hour of time on the ship, two would pass on Earth. A similar situation to the spaceship that orbited the massive black hole.

After another two years of full thrust the ship would reach its top speed, 99 per cent of the speed of light. "At this speed, a single day on board is a whole year of Earth time. Our ship would be truly flying into the future.

"The slowing of time has another benefit. It means we could, in theory, travel extraordinary distances within one lifetime. A trip to the edge of the galaxy would take just 80 years. But the real wonder of our journey is that it reveals just how strange the universe is. It's a universe where time runs at different rates in different places. Where tiny wormholes exist all around us. And where, ultimately, we might use our understanding of physics to become true voyagers through the fourth dimension."