WHEREAS,

1. "Physics Essays", the journal in which these papers are published, has the reputation of being ... on the fringe, let's say;

2. Every single time I have seen a PhysOrg article linked from HN, it has turned out to be at best borderline crackpottery;

3. There is not enough information in the actual article to tell whether this alleged research makes any sense and/or explains anything correctly, but it's full of handwavy stuff that looks very unpromising, and there's no sign of any actual, y'know, physics;

4. The actual publications do not appear to be available for us to read without paying at least $15 to "Physics Essays";

5. On searching for one author (Amrit Sorli) I found, e.g., http://gsjournal.net/eeuro/sorli4.pdf which contains gems like this (in which "QS" stands for "quanta of space"): "One could suppose that consciousness is the basic frequency of QS that build up a-temporal cosmic space. This basic frequency of QS by acting on the neurons of the human brain creates the phenomena of 'human consciousness'. The more the vibrations of the neurons are in tune with the basic frequency of QS, the more person will be conscious. The intensity of the human consciousness depends on the synchronicity with the basic frequency of QS of cosmic space.";

6. The institution with which the authors are affiliated doesn't seem to be one that does any actual science to speak of;

NOW, THEREFORE, I proclaim that this is almost certainly rubbish that isn't worth attending to.

It was the physicists' attempt to explain the mathematical paradox of Achilles and the tortoise using physics (and an unproven physics no less) that tipped me off.

This sounds like someone wrote a highly theoretical physica paper that got filtered through a journalist who had absolutely no idea what it was about, but thought it was cool, and summarized it in very vague and confused terms.

There are a lot of vague philosophical papers without much point to them. Until someone comes up with concrete evidence that this one is different - for instance a specific testable experiment - I would suggest that there is little point in paying much attention to this. Yes, I know that the paper supposedly suggested several such experiments. But the ones mentioned in the summary can ignore time because they are imprecise enough that the speed of light can be regarded as instantaneous. Where more refined versions can be performed, the speed of light shows up as an explicit factor and time dependence is important.

Fitting, since spacetime is the most widely misunderstood concept of physics. n-dimensional vectorspaces is really something most people don't get.

Physics isn't hard because of the maths (n-dim vectorspaces), it's hard because of the physics.

I try to stay educated about modern physics, but this article leaves me scratching my head. The idea that time is just a measure of change, and all we really have is sequences of observations and a causal structure is not new at all. I have seen "timeless" proposals (for instance Julian Barbour's ideas) that seem both more radical and better supported than what I can understand of this summary of the work.

I can't tell if they are proposing something new, or just trying to change some of the vocabulary and mental models we use for current physics.

I feel the same way. What's present in TFA isn't enough to convince me of anything.

What I'm concerned about is this: how does this work with quantum weirdness such as post-selection and entanglement? If I had answers to those questions I might understand what they're proposing. (With a peer-class time dimension I can imagine those two effects in non-spooky ways. Without it they seem hopelessly spooky.)

Time is better implied as a consequence.

For something more enlightening on the subject of the mechanics of time, try this 78 minute Google Tech Talk, "The Origin of the Universe and the Arrow of Time"

http://www.youtube.com/watch?v=GFMfW1jY1xE

A really good introduction to how entropy gives rise to the perception of time passing, as well as a lot of other crazy things.

If you're actually a physicist like many here, you probably won't learn anything new. The nice thing about google tech talks is that they're effectively aimed at software engineers, ie. very clever people that aren't domain experts.

Sean Carroll is a great presenter. I watched the version he presented at University of Sydney: http://www.themonthly.com.au/origin-universe-and-arrow-time-...

I got a lot more out of this talk than I did listening to the audiobook of his arrow of time book. I think I'm giving up on audiobook versions of science books; the voice actors are terrible at it.

Yep, he's great.

Lots more of his talks here: http://preposterousuniverse.com/talks/videos.html

The implications of this theory are interesting.

Let E = {e0, e1, e2, ... en} be the set of all events in the universe, ever. By this hypothesis, the temporal distance between any two adjacent events, that is, the 'amount of time' separating then, is exactly equal. If there is no substrate upon which time is measured, then you cannot say the temporal displacement between e0 and e1 is anything but identical to that between e4 and e5. For that matter, the delay between e1M and e2M precisely equals that between e10M and e11M. This seems utterly bizarre. (edit: corrected grossly mistaken arithmetic, thanks atakan)

By this hypothesis (assuming I'm understanding correctly), there is a "Planck length" of time, which is simply the separation between any adjacent events. It would be meaningless to speak of anything smaller, as there is no substrate upon which to measure the distance between them. It is simply 1. What can it mean to describe a time between two subsequent events but that there is a third between them?

This whole thing is bloody strange, and yet oddly intuitive. Substrates for which there are no direct evidence have a poor record in metaphysics, and I wouldn't be surprised to see a parsimonious rejection of time as a distinct entity follow this trend.

small correction:

"the delay between e10^100 and e10^200 precisely equals that between e10^50 and e10^150"

Between e10^200 and e10^100 there are about 10^200 events, but between e10^50 and e10^150 there are only 10^150. However, I understand what you mean and it is bizarre.

Late night, thanks for the correction.

I found this incomprehensible, possibly because I am ignorant of physics. The type of article that works for me doesn't condescend, but explains the consequences of a new theory in layman's terms, much as a good theory makes predictions that are subject to empirical testing.

Can anyone explain what the consequences of this theory might be? Beyond just saying that spacetime is really just 4D space or that time can be quantized.

Does this change how clocks work? Does it change our beliefs about what happened during the big bang? Does it have any effect on what happens to matter falling into a black hole?

So far as I could read, this proposed new ways of modeling or explaining existing phenomena and a new way of explaining a paradox, but no consequences of any note. And I absolutely couldn't understand the premise that this means time travel is impossible from the article alone.

Was an entire paragraph missing that explained why traveling in four dimensions of space instead of three dimensions of space and one of time means that travelling backwards in time is impossible, in a way that the existing 3D+T model does not prohibit?

Physorg is tabloid nonsense. Why do people keep linking, upvoting this stuff?

Didn't Liebniz come up with this a few hundred years ago?

According to Einstein, time is relative. If I move really fast time is passing slower for me. So time and its effects vary, there should be more than 1 dimension for time in the existing model. Or time should be separated from spatial + other dimensions just because its an outcome of gravity (and other factors) that we cant override and change. This is what Einstein quote is claiming I suppose.

What you are saying makes no sense. Why do you need more than one dimension for time coordinates to express time dilation? How is time an outcome of gravity?!?

>> Why do you need more than one dimension for time coordinates to express time dilation Because in theory, there is no absolute time we can take as reference. 1 year for an object on moon is not 1 year for an object on Jupiter. So time dimension may include other factors that defines itself.

>> How is time an outcome of gravity?!? "General relativity shows that gravity is really not a force, but rather a consequence of the fact that space-time is curved due to the distribution of mass and energy." More on http://www.ram.org/ramblings/science/time_is_relative.html

This then implies that if nothing is moving there is no time. Absolute 0 is timeless. Kinda makes sense.

When something is frozen is there still movement at the subatomic level (electrons orbiting etc) or does that cease too?

Nothing ever stops moving. Ever. To do so would violate the uncertainty principle. So we'll always have time.

But as the Universe approaches 100% entropy, how would you determine the order of events? The only mechanism we have of determining the arrow of time is by measuring increases in entropy.

> To do so would violate the uncertainty principle.

Not if we don't know the exact location of the particle, right?

But you always know at least some information about the location. For example you know it's in the visible universe, which puts an upper bound to its location, and therefor it's momentum.

But don't forget the Time<-->Energy uncertainty. If you know the energy of a particle very exactly you don't know how time will pass for it.

"In the future, the scientists plan to investigate the possibility that quantum space has three dimensions of space, as Sorli explained."

I LOL'd.

My old analogy:

Start with a barter society. Suppose one apple is worth two oranges, and one orange is worth three lemons. Then one apple is worth six lemons. So, say that one lemon is worth one penny. Then one orange is worth three pennies, and one apple is worth six pennies. So, we now have prices for everything.

So, what is one penny? It's a 'common ratio'.

My analogy is the same for time: One tuning fork vibrates at 100 Hz, another at 200 Hz, and another at 600 Hz. So, call one time 'tick' the time of one period of the 600 Hz tuning fork. Then the one period of the 200 Hz tuning fork is three ticks, and, of the 100 Hz tuning fork, six ticks. So, one 'tick' of 'time' is a common ratio.

Seems okay to me.

Except, what if I'm buzzing by your lab at speed c/2. What frequencies will I hear, what will be the relationship of my ticks to your ticks? =)

Same as always: All three tuning forks are close together in the same lab in an inertial frame, etc. You see the same ratios as the lab does. If you compare with some tuning forks on your space ship, then just use special relativity to compare the ticks on your space ship versus the ones in the lab. If the tuning forks are 'standard', say, some spectral lines, the you can see your time dialation.

There is a fourth quantity of some kind - a falling ball is not where it was a moment ago, and you want to be able to express that. The exact nature of this "fourth quantity" is up for debate, though.

So it's like we humans have made up time and it's acting as a mental block to truly understanding what's really going on. Time as a man-made metaphor gives a meaning to our world in a way analogous to religion?

The above thoughts are purely my real-time ramblings, I am clueless but interested :)

We don't understand exactly how gravity works, but I'm pretty confident that being "enlightened" will not allow you to fly. Similarly, although the exact nature of time is apparently up for debate, I'm pretty sure it's not entirely man-made.