Search FQXi


RECENT FORUM POSTS

Joe Fisher: "Dear Potential Realists, Yesterday’s Closer to Truth Facebook page..." in Dissolving Quantum...

Andrea White: "Canon is a leading optical product and imaging product company.They have..." in Sounding the Drums to...

Avneesh panwar: "If you are delete our bing search history to visit this platform delete..." in The Quantum Thermodynamic...

Joe Fisher: "Dear Loyal Reality Followers, The September 14, 2018 Closer to Truth..." in Dissolving Quantum...

Contact Laptop Number UK: "Dial @ 0800-014-8456 toll free in UK for instant HP Laptop Contact Number..." in Usurping Quantum Theory

Contact Printer UK: "Find an instant technical support for HP, Epson, and Canon Printers in UK...." in Constructing a Theory of...

Steve Agnew: "Singh has a really good approach for resolving the measurement issues by..." in Space-time from Collapse...

josef smith: "I would like to thank for the efforts you have Hostgator Promo Codes made..." in Superhuman: Book Review...


RECENT ARTICLES
click titles to read articles

Dissolving Quantum Paradoxes
The impossibility of building a perfect clock could help explain away microscale weirdness.

Constructing a Theory of Life
An all-encompassing framework of physics could help to explain the evolution of consciousness, intelligence, and free will.

Usurping Quantum Theory
The search is on for a fundamental framework that allows for even stranger links between particles than quantum theory—which could lead us to a theory of everything.

Fuzzballs v Black Holes
A radical theory replaces the cosmic crunchers with fuzzy quantum spheres, potentially solving the black-hole information paradox and explaining away the Big Bang and the origin of time.

Whose Physics Is It Anyway? Q&A with Chanda Prescod-Weinstein
Why physics and astronomy communities must take diversity issues seriously in order to do good science.


FQXI ARTICLE
September 19, 2018

Real-Time Physics
Many physicists argue that time is an illusion. Lee Smolin begs to differ.
by Kate Becker
FQXi Awardees: Lee Smolin
April 4, 2011
Bookmark and Share


LEE SMOLIN
Perimeter Institute
Credit: Olivia Mizzi
What if time is real? If you’re not a theoretical physicist, the question being posed by Lee Smolin might sound as silly as if he’d asked: "What if your shoes and socks are real?" You experience them every day; so how could they not be?

Within the world of foundational physics, though, the notion that time might be real is practically radical. Yes, as human beings we experience time as a thing that flows; we mark a divide between the immutable past and the yet-to-be-written future; and we believe we live in a special moment that we call the present, which is constantly being refreshed. Yet according to conventional wisdom—or that peculiar brand of unconventional wisdom that governs quantum physics and cosmology—time is an illusion that emerges from some deeper physics.

In this view, time is a fictitious shorthand for the large-scale behavior of something more fundamental. "It is common in philosophy and science to presume that the things that are deepest and truest about the world are outside of time," summarizes Smolin, a theoretical physicist at the Perimeter Institute in Waterloo, Ontario. "The key question is, is time real or is it an illusion? We experience life as a sequence of moments, but is that the way the world really is?"

Is time real or
is it an illusion?
- Lee Smolin
"There is no question that time exists—we use it everyday," adds Sean Carroll, a physicist at the California Institute of Technology and a prize winner in FQXi’s Nature of Time essay contest. "But we’re not sure whether time is really fundamental—whether it is a necessary part of a deep understanding of physics, or whether it is just a useful approximation."

Smolin wishes to hold on to the reality of time. But to do so, he must overcome a major hurdle: General and special relativity seem to imply the opposite. In the classical Newtonian view, physics operated according to the ticking of an invisible universal clock. But Einstein threw out that master clock when, in his theory of special relativity, he argued that no two events are truly simultaneous unless they are causally related. If simultaneity—the notion of "now"—is relative, the universal clock must be a fiction, and time itself a proxy for the movement and change of objects in the universe. Time is literally written out of the equation.

Although he has spent much of his career exploring the facets of a "timeless" universe, Smolin has become convinced that this is "deeply wrong," he says. He now believes that time is more than just a useful approximation, that it is as real as our guts tell us it is—more real, in fact, than space itself.

The notion of a "real and global time" is the starting hypothesis for Smolin’s new work, which he will undertake this year with two graduate students supported by a $47,500 grant from FQXi. Smolin hopes that this move will allow him to chip away at one of the biggest unsolved problems of physics and cosmology—uniting the laws of quantum physics with the laws of general relativity.

Quantum physics works wonderfully well when applied to atoms and their constituent parts; general relativity is a tried-and-true description of spacetime on the macro scale of planets, stars, and galaxies. When these two sets of laws meet, though, as they must to describe what happens inside a black hole and what the universe was like at the time of the Big Bang, they conflict and break down. Could time be the thread that can stitch them together?

The Cosmic Clock

Smolin hopes that taking time seriously will help to untangle what went on in the early cosmos. At the moment, it is tough to distinguish the laws of nature from the universe’s initial conditions. (By contrast, it’s easy to distinguish between the two in lab experiments because these tests can be repeated with different starting conditions. Cosmologists, however, cannot re-run the universe.)


THE FERMI GAMMA RAY TELESCOPE REVEALS BRIGHT EMISSIONS
IN THE SKY

Could it also uncover the truth about time?
Credit: NASA/DOE/Intl. LAT Team
If he can get a handle on the laws of physics with the help of a fundamental cosmic clock, Smolin can examine the possibility these laws may have been different in the past. The idea that physical laws can evolve over time only makes sense in a framework in which time is fundamental, Smolin argues. To understand why, imagine a soccer game in which the rules are programmed to change every minute. If the clock itself is not fundamental, but is also governed by those fluctuating rules, the poor players and referees would be stuck in an infinite logical loop.

Smolin’s ideas may be unconventional, but others admire his attempts to save time. "Not to do so is to deny the most fundamental data we get from life every day—which also underlies our ability to perform experiments and to analyze theories," says George Ellis, a mathematician at the University of Capetown in South Africa. (George Ellis’ prize-winning FQXi essay “On the Flow of Time” is here.)

However, Carlo Rovelli, a physicist at the University of Marseille, France takes the opposite view: "We must not force theories into our intuition: We change the intuition to understand the theory." (Carlo Rovelli’s prize-winning FQXi essay, "Forget Time" is here.)

Smolin is aware that his theories must be more than philosophically pleasing, if they are to be considered scientific. He notes that astronomers are already using gamma ray telescopes and cosmic ray observatories to probe whether the laws of special relativity still hold at extreme energies. (See "Journeying Through the Quantum Froth.") These experiments have yielded results that constrain some quantum gravity theories. "Though they won’t settle the question of whether time is real," says Smolin, "they do limit the options for theorizing about the nature of time."

Comment on this Article

Please read the important Introduction that governs your participation in this community. Inappropriate language will not be tolerated and posts containing such language will be deleted. Otherwise, this is a free speech Forum and all are welcome!
  • Please enter the text of your post, then click the "Submit New Post" button below. You may also optionally add file attachments below before submitting your edits.

  • HTML tags are not permitted in posts, and will automatically be stripped out. Links to other web sites are permitted. For instructions on how to add links, please read the link help page.

  • You may use superscript (10100) and subscript (A2) using [sup]...[/sup] and [sub]...[/sub] tags.

  • You may use bold (important) and italics (emphasize) using [b]...[/b] and [i]...[/i] tags.

  • You may also include LateX equations into your post.

Insert LaTeX Equation [hide]

LaTeX equations may be displayed in FQXi Forum posts by including them within [equation]...[/equation] tags. You may type your equation directly into your post, or use the LaTeX Equation Preview feature below to see how your equation will render (this is recommended).

For more help on LaTeX, please see the LaTeX Project Home Page.

LaTeX Equation Preview



preview equation
clear equation
insert equation into post at cursor


Your name: (optional)






Recent Comments


I agree with you Ken. Well explained about the Absolute Time. Thanks for the useful information. Cheers!


All,

Is there any empirical evidence that the electron orbitals of an electrically neutral atom carry momentum and/or kinetic energy? Think carefully about what I'm asking and about the implications.

Best Regards,

Gary Simpson


I endorse the idea of Newton’s “absolute time”. However, we have no clock time unit (including a clock second) that represents the same amount of absolute time in different frame. The observer’s clock second represents a specific amount absolute time. According to the Lorentz Transformation this amount of absolute time is represented by 1/gamma seconds on a clock moving with respect to the observer. That’s why a moving clock will accumulate clock seconds at a slower rate than the...

read all article comments

Please enter your e-mail address:
Note: Joining the FQXi mailing list does not give you a login account or constitute membership in the organization.