Time Travel Paradox Lives to Fight Another day

Seth Lloyd of the Massachusetts Institute of Technology and Aephraim Steinberg of the University of Toronto have tested the ‘grandfather paradox’ of time travel by in effect sending a photon back in time to fire a gun which kills it. As perhaps predictable, when the time travel worked the gun failed to go off and when the time travel failed to work the gun went off. Expect further experiments.. (See ‘The quantum time machine, New Scientist, 20 November 2010, pp34/37)

The End of Time May Be Sooner Than We Thought

A team at the Massachusetts Institute of Technology has suggested that in around 5 billion years time, our galaxy might reach the end of time albeit this end of time is a theoretical construct resolving a probability paradox (See ‘Countdown to oblivion’, New Scientist, 2 October 2010, pp6/7)

Small Scale Relativistic Effects on Time Confirmed

James Chin-Wen Chou at NIST has shown that relativity effects on time occur (as predicted) for very small gravitational force changes (33cm higher up) and very small relative speed differences (36 kph). (See ‘Stand on a chair and you’ll age faster’, New Scientist, 2 October 2010, p14)  hide this.

Beyond Einstein – A Direction for Time, Free from Space

Petr Horava, of the University of California, has developed a variant of Einstein’s relativity theories that breaks space-time (Lorentz) symmetry and allows quantum field theory to marry the large and small scales in respect of gravity. Black holes, dark matter and dark energy may all begin to make better sense.
(See ‘The end of space-time’, New Scientist, 7 August 2010, pp28/31)  hide this.

The Most Accurate Clock Yet Under Construction

A clock that uses transitions between energy levels in the nuclei of thorium-229 could improve clock accuracy by a factor of 100. The University of California is growing thorium-229 crystals with a view to using them to accurately check nature’s constants such as the fine-structure constant, alpha.
(See ‘The nuclear option for clocking change’, New Scientist, 5 June 2010, p4)

Time Dilation Not There for Distant Quasars

Time dilation, events appearing to take longer to happen, seems not to be as it should for light reaching us from distant quasars. One explanation is lensing objects, perhaps black holes or dark matter, causing brightness variations affecting how far we think objects are from us.
(See ‘Time slows down for no quasar’, New Scientist, 10 April 2010, p13)

'From Eternity to Here ...' by Sean Carroll

‘From Eternity to Here: The quest for the ultimate theory of time’ by Sean Carroll, seeks to explain the arrow of time, offering a speculative solution based on the idea of a ‘mother space-time’ giving birth to baby universes.
(See ‘Time ain’t what it used to be’, New Scientist, 23 January 2010, p46)  hide this.

Our Internal Clocks are Variable and Malleable

Our internal clocks can have strange effects on our perceptions of movement around us and also on how fast we perform tasks. And they can be manipulated by external sound effects. With their link to psychotic delusions too, a range of useful applications can be imagined
(See ‘The time machine inside your head’, New Scientist, 24 October 2009, pp32/37)

Time Distortion Greater than General relativity’s Expectation

Gravity may distort time much more tan space according to recent analyses of Hubble Space Telescope results. This would be contrary to General relativity expectations of equivalence.
(See ‘Looking for chinks in relativity’s armour’, New Scientist, 24 October 200, pp8/9)

‘Time’, a New Book by Eva Hoffman

Eva Hoffman’s book, ‘Time’, about our changing relationship with time, covers the physics, biology and neuroscience involved.
(See ‘An arrow into the heart of tome’, New Scientist, 17 October 2009, p50)  hide this.

The Keys to Living a Long Time

Avoiding life-shortening ‘environmental’ factors is one thing but, as we get older and survive these, genes become the key and the prospects for understanding what sets one set of genes apart from another are brightening. (See ‘Lessons in longevity’, New Scientist, 5 September 2009, pp42/45) hide this.

Gene Expression Link to Looking Old (or Not)

Gene expression may be significant in how old skin looks. So, because it can be measured, claims of anti-ageing products may be verifiable by measurement of that expression.
(See ‘How genes make our skin look older’, New Scientist, 27 June 2009, p11)

Gene Link to Timing of Human Maturation

A genetic link to the timing of puberty and menopause (and height) for women has been established. Links to voice breaking in boys’ voices is also associated.
(See ‘Genes for timing at puberty and menopause found’, New Scientist, 23 May 2009, p15) hide this.

Déjà vu

Research into déjà vu continues with some thinking around it being just similar environments giving a sense of familiarity. Other thinking is that the brain can create a sense of familiarity without having any prior experience. Our perception of time may also be involved when a glimpse of something without recognition is then seen with recognition a short time later but perceived to have been seen at some much earlier time. Déjà vu feels wrong because of the contradiction between our rational and emotional thinking.
(See ‘Déjà vu all over again’, New Scientist, 28 March 2009, pp28/31)

Big Ben Anniversary PR

May 2009 marks the 150th anniversary of when Big Ben’s clock began to keep time and a PR exercise is underway to mark this and its symbolism in the wider world.
(See ‘Big Ben gats ready to ring the changes’, Observer, 15 March 2009)

The Secret of Long Life?

Scientists have identified a piece of DNA in swifts that predicts how long they will live. These ‘telemores’, at the ends of chromosomes, are also present in humans and they erode over time. So keeping them long may prolong life.
(See ‘Swifts may hold secret of staying young’, Observer, 15 March 2009)

Smaller Most Accurate Clocks On The Way

Large cubic-metre sized clocks accommodating microwave and caesium filled vacuum clocks have to date been the most accurate clocks. But they may be replaced soon by much smaller (and more accurate) clocks using lasers instead of microwaves and aluminium, instead of caesium, held in a micro-metre sized space.
(See ‘It’s time to measure seconds even more accurately’, New Scientist, 14 March 2009, p20)

Major Time Measurement Advances Hugely Useful

Scientists have been pushing forward the precision of time measurement with caesium based clocks holding sway much of the time but an aluminium atom based clock is now accurate to 1 second in 650 million years. Time measurement is moving to a stage where it can test the constancy of universal constants and dramatically improve GPS accuracy.
(See ‘Every second counts, New Scientist, 7 February 2009, pp39/42)

Time in Antiquity

This is Robert Hannah’s new book on the Greeks’ and Romans’ measuring of time and its links with cosmic cycles – of the sun, moon and stars.
(See ‘Changing Time, New Scientist, 31 January 2009, p45)

Rome’s Pantheon Designed to be Huge Sundial?

The oculus, a circular opening, in the centre of the dome of Rome’s Pantheon casts light through a grille into an external courtyard only at the two equinoxes suggesting that the building was designed to operate as a huge sundial.
(See ‘Is this the boldest sundial ever built?’, New Scientist, 31 January 2009, p12)

Gravity behind Time’s Arrow?

The ‘switching on of gravity may have given rise to the arrow of time by creating the order (low entropy) so that an increase in disorder (entropy) is an inevitable process. What the arrow of time was and why before gravity kicked in remains unclear.
(See ‘Did gravity kick start time’s arrow’, New Scientist, 3 January 2009, p9)  hide this.

Pendulum Hotspots Everywhere

Weird hotspots (‘breathers’) of vibration in systems of linked vibratable parts (including within solids) may be widespread and explain phenomena that have defied explanation to date. The effect can be seen in simple chains of pendulum. (see ‘The swing of things’, New Scientist, 2 December 2006, pp 44/47)

A Day for what takes Earth a Year to do

Planets have been found that are travelling round their host stars in less than 24 hours compared with the year the Earth takes to go round the sun. (See ‘Years that pass in less than a day’, New Scientist, 7 October 2006, p16)

Body Clock Change Problems

Age related body clock changes cause a range of problems. Young ‘morning’ children for instance become ‘evening’ teenagers suffering from sleep deprivation and its impacts (smoking, depression, anxiety, obesity, …). But how and why this happens is not fully understood. (See ‘It came from another time zone’, New Scientist, 2 September 2006, pp 40/43)

Clock Genes Switched on by Odd Eating Times

Eating at odd times can switch on clock genes that then activate you to be ready for those times subsequently, with disordering results. (See ‘Mouse munchies’, New Scientist, 5 August 2006, p 17)

A Body Clock in the Adrenal Glands

The adrenal glands above our kidneys have been found to host rhythmic 24 hour fluctuations in gene activity which may be associated with the release of mood altering hormones such as to promote activity or sleepiness. (See ‘Time for bed, said the adrenal clock’, New Scientist, 3 June 2006, p 19)

Faster than the Speed of Light and Back in Time

If the universe is a 4-dimensional brane floating in 10-dimensional space-time then there may be short cuts through higher dimensions that make time travel possible. And in these higher dimensions, special relativity may not apply and things could travel faster than light. An experiment to test this has been postulated. (See ‘Head ‘em off at the past’, New Scientist, 20 May 2006, pp 34/37)

Octogenarian Time Check

In the early 20th Century an octogenarian spinster, Ruth Belville, used to carry time on a chronometer from the Royal Observatory at Greenwich to people across London who would otherwise have to set their clocks by sundials. (see ‘The Lady Who Sold Time’, New Scientist, 25 February 2006, pp 52/53)

Time Flies or Not

There is great flexibility in how we perceive the passage of time. However perceptions and estimation of time are non-intuitively different and inaccurate. And much uncertainty about the issue remains. (See ‘The 25 hour day’, New Scientist, 4 February 2006, p 34)

Slower Human Molecular Clock Linked to Later Breeding

Our molecular clock (rate of mutation accumulation) are slower than other apes and may have been caused by the increase in our generation times about a million years ago. (See ‘Live fast, breed young, say apes’, New Scientist, 28 January 2006, p 17) hide this.

From ‘A Matter of Time’, Scientific American – Special Edition (Vol.16, No.1, 2006)

The Essence of Time

We can dissect it to attoseconds and measure deep time. We live by it (instant messaging, one-hour photos, express checkout, same-day delivery). Yet struggle to understand it. (See ‘Real Time’, pp 2/5)

Time Flows and Flies

Augustine remarked that he knew what time was until somebody asked. We are all in the same boat. All we know is that later states are different from earlier ones – that we remember. Simultaneity depends on where you are and how fast you are going. (See ‘That Mysterious flow’ pp 6/11)

Philosophy and Time

Philosophy can contribute to understanding the problems of time, for example around the relationism vs the substantivalism approaches to time or the role of thermodynamics in explaining the arrow of time. (See ‘A Hole at the Heart of Physics’ pp12/13)

Time Travel

Travelling forward in time can be achieved be travelling close to the speed of light. Travelling backwards in time is trickier. Wormholes are postulated that the next generation of particle accelerators could conceivably create. (See ‘How to Build a Time Machine’ pp14/19)

Staying Young

Travel close to the speed of light and you’ll have aged less than those who haven’t. Decaying muons can last 30 times as long when travelling within a whisker of the speed of light. The Twin paradox is a reality. (See ‘Time and the Twin Paradox’ pp 20/23)

Biological Clocks

Part of our Brain can track seconds, minutes and hours. Another part can synchronise our functions to days and seasons. Our lifespan may be governed by telomeres which shrink with every cell division. (See ‘Times of our Lives’ pp 26/33)

Remembering When

We experience time very variably and damage to certain parts of the brain can remove one’s entire sense of time. (See ‘Remembering When’ pp 34/41)

Did Time Begin at the Big Bang?

The useful notion of the inflationary universe is? Some problems associated with it. Two approaches to get round these are loop-quantum gravity and sting theory. Both these approaches open up the possibility of a pre-Bang universe, time existing before the Big Bang (See ‘The Myth of the Beginning of Time’ pp 72/90) hide this.

Seeing Through to the Very Beginning

Asantha Cooray of the University of California at Irvine and Kris Sigurdson at the Institute for Advanced Study in Princeton, New Jersey have begun testing a new way to probe the very beginning of time. Cosmic microwave background radiation can be disturbed and made to look like the inflationary gravitational waves (IGWs) from the beginning of the Universe. In order to avoid this interference, so they can find real traces of IGWs, the team are going to measure interference in other, uniform, waves and then remove interference in the microwave background radiation. When this is complete, questions about the beginning of time could be answered. (See ‘Where to find the beginning of time’, New Scientist, 26 November 2005, p 16)

Quantum Theory Prevents Time Travel Paradoxes

The laws of Physics allow time travel according to Daniel Greenberger of the City University of New York and Karl Svozil of the Vienna University of Technology. Quantum mechanics, whilst allowing time travel, only permits a time traveller to observe the pasts consistent with the world they have just come from. Thus, the traditional paradoxes can never occur if you travel back in time quantum mechanically. (See ‘No Paradox for Time Travellers’, New Scientist, 18 June 2005, p 15)

Old Japanese Clock Masterpiece Ticks Again

An old Japanese clock that stopped ticking in 1851 has been restored by a team of engineers, craftsmen and scientists from Toshiba and the Japanese Science Museum. The Clock inventor (and later founder of Toshiba) was Hisashige Tanaka. It is called Man-nen dokei which means ‘the clock for 10,000 years’ and tells the time in different ways: The phases of the moon, oriental Zodiac, Japan’s old 24 phase division of the lunar year, Days of the week, Japan’s traditional way of dividing daylight and nights and the standard western way. (See ’10,000-year Japanese clock springs back to life’, New Scientist, 19 March 2005, p 25)

Universes Allow Observer Destroying Super-Tasking

Super-tasking, in which a machine performs a function in ½ a minute then ¼ then ⅛ etc… potentially allows for an infinite number of functions to be carried out in a finite length of time. However, only pseudo super-tasking is actually allowed by the laws of relativity where a man moving away at high speed will appear to a stationary observer to be performing infinite tasks in finite time. Unfortunately, practical considerations mean the stationary observer would never actually be able to study the information created by the machine without being annihilated. (See ‘How to do an infinite number of things before breakfast’, New Scientist, 29 January 2005, p 28) hide this.

Defective Time Gene and Over-Drinking Link

Locking people into permanent jet-lag may explain why some people drink too much. (See ‘Faulty body clock can drive you to drink’, New Scientist, 25 December 2004, p 9)

The Eclipse and the Pendulum

Pendulum irregularities at the onset of total eclipses are thought by some to require a re-look at gravitational theory. But environmental eclipse factors may be behind the effects. (See ‘Shadow over gravity’, New Scientist, 27 November 2004, pp 28/31)

Time Gene Alterations Change Track of Time

Impairing the ‘timeless’ and ‘period’ clock genes in male fruit flies caused them to mate 30% longer than normal. (See ‘Time flies …’, New Scientist, 28 August 2004, p 14)

Time Kept by Flip-Flopping Proteins

Flip-Flopping proteins (flipping from one form to another and then back again) may play a key role in the body’s timekeeping with flip-flopping also becoming synchronised within preparations. (See ‘The shapeshifters’, New Scientist, 17 July 2004, pp 30/33)

Mitochondrial Mutation Advances Ageing

Accelerating the mitochondrial mutation rate thought to be a factor in ageing had caused mice with deliberately defective mitochondrial DNA to age rapidly. It remains unclear how the mitochondria trigger ageing in tissues. (See ‘Fast ageing reveals secrets of youth’, New Scientist, 29 May 2004, p 14)

Multiple Applications of Time Reversed Microwaves

Microwaves, time-reversed (last in first out) by a detector using a cunning sampling technique, can be focused on a variety of potential applications in medicine, communications etc… (See ‘Time reversal trick perfected for microwaves’, New Scientist, 29 May 2004, p 12)

Information Handling behind Time’s Arrow

Our sense that there is a ‘now’ and that time flows from the past, through present, and into the future is determined by evolutionary pressures and relates to how we receive store and forget information. It might be possible to build a robot that understands time backwards, remembering the future and forgetting the past. (See ‘Clock-watchers’, New Scientist, 1 May 2004, pp 34/37)

Time Entanglement

Caslar Bruckner of the University of Vienna has shown that moments in time can become entangled as well as widely separated particles. The very act of measuring a photon’s polarisation a second time can affect how it was polarised earlier on. (See ‘The weirdest link’, New Scientist, 27 March 2004, pp 32/35)

The Big Bang – A portal from a Prior Mirror Image Universe

To believe that the Big Bang is the first moment of time is more religious mysticism than science. A theory called loop quantum gravity, an alternative to string theory, sees the universe as made up of tiny loops. The theory doesn’t break down at the Big Bang but can be rolled back to a time before it and a contracting mirror image universe. (See ‘The world turned inside out’, New Scientist, 20 March 2004, pp.34/37) hide this.

Time and Space

Paul Davies writes: Peter Lynds’s reasonable and widely accepted assertion that the flow of time is an illusion does not imply that time itself is an illusion. It is perfectly meaningful to state that two events may be separated by a certain duration, while denying that time mysteriously flows from one event to the other. Crick compares our perception of time to that of space. Quite right. Space does not flow either, but it’s still “there”. (See ‘Time and Space’, Letters, New Scientist, 6 December 2003, p.34)

Bug causes a Fast Forward (and Back) of Time

A temporal glitch was about to send millions of people prematurely into the next day. Is it only a matter of time before another mix-up causes disaster? A Motorola bug caused by an extra second being slipped into the calendar was to cause a date change of one second after midnight on the morning of 28th November. (See ‘Time Warp’, New Scientist, 22 November 2003, pp.30/33)

A New Mathematics Matching our Sense of the Flow of Time

‘Causal set theory’ can allow space-time to grow in such a way that time appears to flow rather than being a static dimension. It could reconcile science with our deep sense of the reality of the passage of time. (See ‘Real time’, New Scientist, 4 October 2003, pp.36/39)

Time Travel Obstacles

General relativity doesn’t rule out time travel so paradox avoidance leads us to the likes of Stephen Hawking’s “chronology protection conjecture” or concern that the theory of general relativity is incomplete. At present the theory is open to a multitude of different opportunities for time travel. But real time travel may be prevented by the separation of reality and illusion indicated by application of the holographic principle. Or the ‘opportunities’ may break down and not behave as expected before the point at which time travel would be possible. (See ‘No going back’, New Scientist, 20 September 2003, pp.28)

A New Way to Model Real World Stop-Start Change

‘Time scale calculus’ bridges the divide between the discrete and continuous so helping model stop start temporal change reality such as that of West Nile virus mosquito populations. (See ‘Taming nature’s numbers, New Scientist, 19 July 2003, pp.28/31)

When our Attention is Switched on, Time seems to Slow and we can Measure it

Time is perceived to slow down when our attention, hearing or vision, is suddenly switched on. Scientists have been able to measure how much attention grabbing events slow down our perception of time. (See ‘Time drags when danger looms’, New Scientist, 2 November 2003, p.21) hide this.

Scientists are Developing the Most Accurate Clock Yet

Researchers have been working on a clock using mercury ions which emit waves at high frequency. Such a clock should lose only one second in 150 million years and could replace clocks currently used as national standards. (See ‘Mercury clock could set the standard’, New Scientist, 12 October 2002)

Internal Avalanches Make the Earth Spin Faster

Every now and again (200 million years or so) the Earth’s spin suddenly increases against the general trend of a gradual slowing down. Deep-Earth avalanches of cold, dense chunks of the upper mantle occurring when the transition zone below it becomes unstable could be the cause. (See ‘Wind-Up’, New Scientist, 23 November 2002, pp.30/33)

British Time Goes off the Air

Time stood still in Britain in April 2002 when the mast transmitting the official time signal had to be closed down for repairs. Users had to switch to the American GPS network which also broadcasts an atomic clock based time signal. (See ‘The time is precisely, erm, hold on …’, New Scientist, 13 April 2002, p.14) hide this.