# If time is an illusion

**URL:** <https://boards.straightdope.com/t/if-time-is-an-illusion/284351>\
**Category:** Great Debates\
**Created:** [January 12, 2005, 5:33am UTC](https://boards.straightdope.com/t/if-time-is-an-illusion/284351 "2005-01-12T05:33:48Z")\
**Posts on this page:** 20\
**Page:** 1

<div class="post-metadata">

**Author:** ![Nobody](https://avatars.discourse-cdn.com/v4/letter/n/94ad74/32.png) [@Nobody](https://boards.straightdope.com/u/Nobody)\
**Post date:** [January 12, 2005, 5:33am UTC](https://boards.straightdope.com/t/if-time-is-an-illusion/284351/1 "2005-01-12T05:33:48Z")

</div>

My appologies if this thread is in the wrong forum, I’m not sure where to put it.

OK, three questions for those who believe that time is an illusion, or, if you don’t, then I’d appreciate it if you do post, to post from the point of view of someone who believes that it is.

Question one. I’ve heard it stated that it’s believed that time, along with space, was created with the Big Bang\*.  
OK, the commonly accepted definition of an illusion is something that seems to be real, but isn’t. So, illusions are then, fake.  
So if time is an illusion, that means it’s fake, right? And so, does the belief in time being an illusion conflict with the belief that time was created at the big bang, since, something that does not exist cannot be created? Well, illusions can be created, but if time itself is an illusion, then that means that it actually really wasn’t created, right?

Question two. If time is an illusion, then we don’t live in a four dimensional timespace then, right? We just live in a three or more spatial dimension only, right?

Finally, if time is an illusion, then would that mean that everything that was, is, and will be has, and always will exist, and there is no beginning or end of time?

Thanks.

---

<div class="post-metadata">

**Author:** ![Nobody](https://avatars.discourse-cdn.com/v4/letter/n/94ad74/32.png) [@Nobody](https://boards.straightdope.com/u/Nobody)\
**Post date:** [January 12, 2005, 5:35am UTC](https://boards.straightdope.com/t/if-time-is-an-illusion/284351/2 "2005-01-12T05:35:36Z")

</div>

Oops, the \* after big bang ment I was going to say at the bottom of the screen that I know that the term “Big Bang” isn’t entirely accurate, but I’m not sure what the current terminology is.

---

<div class="post-metadata">

**Author:** ![The\_Cat](https://avatars.discourse-cdn.com/v4/letter/t/b9bd4f/32.png) [@The\_Cat](https://boards.straightdope.com/u/The_Cat)\
**Post date:** [January 12, 2005, 5:43am UTC](https://boards.straightdope.com/t/if-time-is-an-illusion/284351/3 "2005-01-12T05:43:42Z")

</div>

Time is construct of the human mind. Imagine I take one watch and put it in orbit around the earth and wear an identical watch. The watch in orbit will run slower than the watch I’m wearing. This is because the watch in orbit is in a different reference frame than I am.

Imagine we’re both in LA wearing identical synchronized watchesand I drive to New York, because we are in different reference frames and I accelerated away from you my watch will be slightly behind your watch when I get back. The time dilation will not be noticeable however. IT will be MUCH MUCH MUCH less than a second.

Just in case your wondering these are not just a mind exercises. It can be tested and proven. When you float a sattelite you have to account for this difference in time. Here on earth we do live in 4 dimensional space time. It just doesn’t matter because the time dilations we see are so small that they become insignificant.

---

<div class="post-metadata">

**Author:** ![Taber](https://avatars.discourse-cdn.com/v4/letter/t/ac91a4/32.png) [@Taber](https://boards.straightdope.com/u/Taber)\
**Post date:** [January 12, 2005, 5:59am UTC](https://boards.straightdope.com/t/if-time-is-an-illusion/284351/4 "2005-01-12T05:59:24Z")

</div>

> [@Master Control](#):
>
> Question two. If time is an illusion, then we don’t live in a four dimensional timespace then, right? We just live in a three or more spatial dimension only, right?

I’m not sure what this whole “time is an illusion” thing, but I think you misunderstand what people mean when they say that time is the fourth dimension.

The fourth dimension isn’t actually time, but it can only be revealed by time. Imagine a 2-D being, that lived in length and width, and had no way of knowing about depth. Imagine a human met this 2-D being, and the human wanted the 2-D being to see the entirety of the human.

so the human would lower or raise himself slowly, until every part of him was in the plane the the 2-D guy existed on. From the 2-D guy’s perspective, the human would be two foot print shaped things that would slowly shrink into two ovals. The ovals would grow until the 2-D being got to waist level, and so on.

The point being, depth is not time, but the 2-D being saw the human’s depth as a series of changes in time.

someone can correct me on this, it has been awhile since this was explained to me, I may have gotten something wrong

---

<div class="post-metadata">

**Author:** ![SentientMeat](https://avatars.discourse-cdn.com/v4/letter/s/43a26b/32.png) [@SentientMeat](https://boards.straightdope.com/u/SentientMeat)\
**Post date:** [January 12, 2005, 10:15am UTC](https://boards.straightdope.com/t/if-time-is-an-illusion/284351/5 "2005-01-12T10:15:40Z")

</div>

> [@](#):
>
> Question one. I’ve heard it stated that it’s believed that time, along with space, was created with the Big Bang\*.

It was not “created”. There was no “nothing-to-something” transition or event. The universe has [always existed](http://boards.straightdope.com/sdmb/showthread.php?threadid=203743), and the initial state of the universe may be one of _timelessness_.

> [@](#):
>
> OK, the commonly accepted definition of an illusion is something that seems to be real, but isn’t. So, illusions are then, fake.

That might be a little harsh - I would suggest “not what it seems” is more accurate. A rainbow seems to be a multicoloured bridge to the sky, but we know it to be an optical _illusion_ caused by the prismatic effect of water droplets on white sunlight: is a rainbow a ‘fake’?

> [@](#):
>
> So if time is an illusion, that means it’s fake, right? And so, does the belief in time being an illusion conflict with the belief that time was created at the big bang, since, something that does not exist cannot be created? Well, illusions can be created, but if time itself is an illusion, then that means that it actually really wasn’t created, right?

I think this is what’s called a ‘[category error](http://en.wikipedia.org/wiki/Category_mistake)’.

> [@](#):
>
> Question two. If time is an illusion, then we don’t live in a four dimensional timespace then, right? We just live in a three or more spatial dimension only, right?

The idea that time is an illusion is more to do with the idea that there **is** some “other axis” on which events can be plotted (_“Time is what prevents everything from happening at once.” - John Wheeler_), but that this is **static** (_ie._ there is no “now”, all configurations of the universe from the Big Bang to the Big Crunch simply **exist** ). In this way, the time axis is not _eliminated_, it is simply treated like another dimension of space such that, say, last Tuesday, “today”, and next Tuesday are different _places_ in the universe, and next Tuesdays events exist in precisely the same way as last Tuesday’s: “today” can simply have no _knowledge_ of them.

> [@](#):
>
> Finally, if time is an illusion, then would that mean that everything that was, is, and will be has, and always will exist, and there is no beginning or end of time?

Yep. We happen to live in ‘time’, whatever it is. We happen to live on Earth. When you ask “is there a beginning or end of time?”, how might one answer the question “is there a beginning or end of the sphere called Earth?”.

---

<div class="post-metadata">

**Author:** ![SentientMeat](https://avatars.discourse-cdn.com/v4/letter/s/43a26b/32.png) [@SentientMeat](https://boards.straightdope.com/u/SentientMeat)\
**Post date:** [January 12, 2005, 10:17am UTC](https://boards.straightdope.com/t/if-time-is-an-illusion/284351/6 "2005-01-12T10:17:51Z")

</div>

And of course, there is another essential quote here:

> [@](#):
>
> **Douglas Adams’ “Hitchiker’s Guide to the Galaxy”** :  
> _“Time is an illusion, lunchtime doubly so.”_

---

<div class="post-metadata">

**Author:** ![Liberal](https://avatars.discourse-cdn.com/v4/letter/l/848f3c/32.png) [@Liberal](https://boards.straightdope.com/u/Liberal)\
**Post date:** [January 12, 2005, 10:28am UTC](https://boards.straightdope.com/t/if-time-is-an-illusion/284351/7 "2005-01-12T10:28:57Z")

</div>

> [@Sentient](#):
>
> It was not “created”. There was no “nothing-to-something” transition or event. The universe has always existed, and the initial state of the universe may be one of timelessness.

Hoo boy, here we go. 😉

What scientific evidence is there that the initial state of the universe was one of timelessness? And what does “timeless” mean mathematically; i.e., what is it a function of, or what is its value in an equation with “t”?

---

<div class="post-metadata">

**Author:** ![SentientMeat](https://avatars.discourse-cdn.com/v4/letter/s/43a26b/32.png) [@SentientMeat](https://boards.straightdope.com/u/SentientMeat)\
**Post date:** [January 12, 2005, 10:55am UTC](https://boards.straightdope.com/t/if-time-is-an-illusion/284351/8 "2005-01-12T10:55:35Z")

</div>

> [@](#):
>
> What scientific evidence is there that the initial state of the universe was one of timelessness?

None directly, indeed there may _never_ be any. However, once we follow the expansion of the universe back to when it approaches the [Planck length](http://en.wikipedia.org/wiki/Planck_length) and get within the [Planck time](http://en.wikipedia.org/wiki/Planck_time) of the point we are calling “t=0”, one cannot say that one can go any “further back”. It _might_ be that other “lines of time” are “attached” to that initial singularity, but we could never access them - they might as well be considered other _regions_ of the universe which we could never visit. “Timeless singularity” (or singularity-type object, since the universe may never have been literally zero in size even though it may have been smaller than the Planck length) is a far more accurate way of describing one end of our region of the universe than the term of ridicule “Big Bang” (it wasn’t big and it wasn’t a bang).

> [@](#):
>
> And what does “timeless” mean mathematically; i.e., what is it a function of, or what is its value in an equation with “t”?

f[sub]t\<0[/sub]=f[sub]t=0[/sub], where f is the configuration of the universe (over however many dimensions!)

---

<div class="post-metadata">

**Author:** ![Liberal](https://avatars.discourse-cdn.com/v4/letter/l/848f3c/32.png) [@Liberal](https://boards.straightdope.com/u/Liberal)\
**Post date:** [January 12, 2005, 11:10am UTC](https://boards.straightdope.com/t/if-time-is-an-illusion/284351/9 "2005-01-12T11:10:57Z")

</div>

> [@Sentient](#):
>
> None directly, indeed there may never be any.

Okay, fair enough — so long as we all are on the same page that what is going on here is philosophical speculation.

> [@](#):
>
> However, once we follow the expansion of the universe back to when it approaches the Planck length and get within the Planck time of the point we are calling “t=0”, one cannot say that one can go any “further back”.

Why not? Why can’t t=-1?

> [@](#):
>
> It might be that other “lines of time” are “attached” to that initial singularity, but we could never access them - they might as well be considered other regions of the universe which we could never visit.

Why posit entities that are not even accessible and cannot be tested?

> [@](#):
>
> “Timeless singularity” (or singularity-type object, since the universe may never have been literally zero in size even though it may have been smaller than the Planck length) is a far more accurate way of describing one end of our region of the universe than the term of ridicule “Big Bang” (it wasn’t big and it wasn’t a bang).

If all this is so accurate, why is it peppered with quotation marks? “Further back”, “line of time”, “attached”, “timeless singularity”, and so on.

> [@](#):
>
> f[sub]t\<0[/sub]=f[sub]t=0[/sub], where f is the configuration of the universe (over however many dimensions!)

I don’t understand the equation, much less the value of t. Is it saying that timelessness is both less than zero and equal to zero?

---

<div class="post-metadata">

**Author:** ![SentientMeat](https://avatars.discourse-cdn.com/v4/letter/s/43a26b/32.png) [@SentientMeat](https://boards.straightdope.com/u/SentientMeat)\
**Post date:** [January 12, 2005, 12:06pm UTC](https://boards.straightdope.com/t/if-time-is-an-illusion/284351/10 "2005-01-12T12:06:18Z")

</div>

> [@](#):
>
> Okay, fair enough — so long as we all are on the same page that what is going on here is philosophical speculation.

Not quite _so_ abtract, I would suggest: everything must still be _consistent_ with General Relativity and Quantum Mechanics, and hypotheses like [inflation](http://nedwww.ipac.caltech.edu/level5/Guth/Guth3.html) (coincidentally from the current GQ, presumably soon to be GD thread) **do** have observable consequences which give us confidence that we are not making it up as we go along from whole cloth.

> [@](#):
>
> Why not? Why can’t t=-1?

Why can’t I juggle -3 oranges?

> [@](#):
>
> Why posit entities that are not even accessible and cannot be tested?

A useful analogy is [supergravity](http://en.wikipedia.org/wiki/Supergravity) (or, further, [M](http://en.wikipedia.org/wiki/M_theory) Theory), whereby more dimensions than “our” simple 3 of space and one of time are posited in order to _explain_ what we see in “ours”. If such a theory makes staggeringly accurate and non-circular predictions about what we _do_ see, it would be as useful an explanatory entity as Einstein’s General Relativity. Hence the “other timelines” model be _tested_ even though those timelines might not necessarily be directly tested _for_. However, the model always comes _before_ the possible testable consequences: we are already forced to spend billions of dollars building enormous synchrotrons to actually _test_ some models in physics. If our physics slips from the grasp of our engineering, we could still have confidence in its _consistency_ with well-tested theories.

> [@](#):
>
> If all this is so accurate, why is it peppered with quotation marks? “Further back”, “line of time”, “attached”, “timeless singularity”, and so on.

I said _more_ accurate than other terms. Remove the inverted commas if you like - I thought they might be useful in diversting ourselves of this thing called time, or at least exploring its nature.

> [@](#):
>
> I don’t understand the equation, much less the value of t. Is it saying that timelessness is both less than zero and equal to zero?

My hugely oversimplified equation represented the idea that the configuration of the universe at t=0 is precisely the same as that for any other value of t less than 0 because the function is _undefined_ for t less than 0, just as North is undefined for \<0[sup]o[/sup] latitude. That does not mean that the universe is carrying on doing all these unobservable undefined things for t\<0 anymore than there is a mysterious Land of UltraNorth at -3 degrees latitude. Timelessness is identical to an infinite amount of time without _change_. I argue that it is far more intellectually graspable not to simply rattle off that “t\<0 is undefined” (which is nevertheless accurate) but to consider the state at t=0 to be identical to all times between -infinity and 0.

---

<div class="post-metadata">

**Author:** ![SentientMeat](https://avatars.discourse-cdn.com/v4/letter/s/43a26b/32.png) [@SentientMeat](https://boards.straightdope.com/u/SentientMeat)\
**Post date:** [January 12, 2005, 2:53pm UTC](https://boards.straightdope.com/t/if-time-is-an-illusion/284351/11 "2005-01-12T14:53:23Z")

</div>

> [@](#):
>
> Why not? Why can’t t=-1?

Actually, perhaps my response to this question above was a little glib - I’ll try again.

Let us look at why the grumpy old [steady-state](http://en.wikipedia.org/wiki/Steady_state)-believing Yorkshireman Fred Hoyle coined the term of abuse “Big Bang” in the first place. Hubble’s obsevation of receding galaxies and the subsequent discovery of the [cosmic microwave background](http://en.wikipedia.org/wiki/CMB) show that the universe is undeniably **expanding**. So, as we rewind the tape further and further back, we get to the point where the universe is incredibly small, perhaps _infinitely_ small, at or near t=0.

Now, time and space are related according to Einstein’s Relativity. We are so used to thinking that “time goes on” that we struggle to divest ourselves of the notion. However, what can accurately be described as timelessness _does_ occur under Special Relativity (a photon’s frame of reference) and General Relativity (within the event horizon of a black hole). Is there any reason it _could not_ describe the state of the universe at t=0?

**Lib** quite reasonably asks “What about t\<0?”. Think of the universe shrinking on that rewound tape - to go any further back would have us asking “What about when the size of the universe is **smaller than zero**?” This is a question that we simply do not ask, even though it is every bit as reasonable as “What about t\<0?”. Why is that?

It is because in our everyday lives we understand that things can’t be smaller than nothing. But our everyday lives are contingent on _change_, on _time_ - we simply can’t imagine that it might not “go on” indefinitely, since we have no experience of travelling at 300,000 km per second or sitting in a black hole.

So, to answer more thoroughly: t could only equal -1 seconds if the universe could shrink until it was -300,000 km wide. I’d suggest just pretending it was the same size at t=-1 as it was at t=0.

---

<div class="post-metadata">

**Author:** ![Nobody](https://avatars.discourse-cdn.com/v4/letter/n/94ad74/32.png) [@Nobody](https://boards.straightdope.com/u/Nobody)\
**Post date:** [January 13, 2005, 1:19am UTC](https://boards.straightdope.com/t/if-time-is-an-illusion/284351/12 "2005-01-13T01:19:56Z")

</div>

> [@Taber](#):
>
> I’m not sure what this whole “time is an illusion” thing, but I think you misunderstand what people mean when they say that time is the fourth dimension.
> 
> The fourth dimension isn’t actually time, but it can only be revealed by time. Imagine a 2-D being, that lived in length and width, and had no way of knowing about depth. Imagine a human met this 2-D being, and the human wanted the 2-D being to see the entirety of the human.
> 
> so the human would lower or raise himself slowly, until every part of him was in the plane the the 2-D guy existed on. From the 2-D guy’s perspective, the human would be two foot print shaped things that would slowly shrink into two ovals. The ovals would grow until the 2-D being got to waist level, and so on.
> 
> The point being, depth is not time, but the 2-D being saw the human’s depth as a series of changes in time.
> 
> someone can correct me on this, it has been awhile since this was explained to me, I may have gotten something wrong

I am well aware of spatial dimensions. I’ve read Flatland and have studied up on tesseracts and hyperspheres.  
What I’m talking about is what some refer to as four dimensional space-time. The space, being of course the three spatial dimensions that we can perceive, and time, being the fourth dimension. Of course time isn’t a spatial dimension, but it is a dimension and can be measured.

---

<div class="post-metadata">

**Author:** ![Nobody](https://avatars.discourse-cdn.com/v4/letter/n/94ad74/32.png) [@Nobody](https://boards.straightdope.com/u/Nobody)\
**Post date:** [January 13, 2005, 1:21am UTC](https://boards.straightdope.com/t/if-time-is-an-illusion/284351/13 "2005-01-13T01:21:08Z")

</div>

> [@The Cat](#):
>
> Time is construct of the human mind. Imagine I take one watch and put it in orbit around the earth and wear an identical watch. The watch in orbit will run slower than the watch I’m wearing. This is because the watch in orbit is in a different reference frame than I am.
> 
> Imagine we’re both in LA wearing identical synchronized watchesand I drive to New York, because we are in different reference frames and I accelerated away from you my watch will be slightly behind your watch when I get back. The time dilation will not be noticeable however. IT will be MUCH MUCH MUCH less than a second.
> 
> Just in case your wondering these are not just a mind exercises. It can be tested and proven. When you float a sattelite you have to account for this difference in time. Here on earth we do live in 4 dimensional space time. It just doesn’t matter because the time dilations we see are so small that they become insignificant.

Yeah, the closer to the speed of light you go, the slower time goes. But how does this prove that time is an illusion?

---

<div class="post-metadata">

**Author:** ![Nobody](https://avatars.discourse-cdn.com/v4/letter/n/94ad74/32.png) [@Nobody](https://boards.straightdope.com/u/Nobody)\
**Post date:** [January 13, 2005, 1:49am UTC](https://boards.straightdope.com/t/if-time-is-an-illusion/284351/14 "2005-01-13T01:49:07Z")

</div>

> [@SentientMeat](#):
>
> It was not “created”. There was no “nothing-to-something” transition or event. The universe has [always existed](http://boards.straightdope.com/sdmb/showthread.php?threadid=203743), and the initial state of the universe may be one of _timelessness_.

Those were some interesting points you made in that thread. I’d say more, but to reply to what you wrote… I don’t think I could do it without making a very, very, long post, so I’ll just repete that that was very interesting.

> [@](#):
>
> That might be a little harsh - I would suggest “not what it seems” is more accurate. A rainbow seems to be a multicoloured bridge to the sky, but we know it to be an optical _illusion_ caused by the prismatic effect of water droplets on white sunlight: is a rainbow a ‘fake’?

That is an excellent point. I personally don’t believe that time is fake, and probably never will. As for being what it seems, for me, that’s more of a problem, because I personally haven’t arrived at what time is…well, that’s not exactly true…let’s just say that this is another topic that would require an extremely long post to express my thoughts and opinions on the matter.

> [@](#):
>
> The idea that time is an illusion is more to do with the idea that there **is** some “other axis” on which events can be plotted (_“Time is what prevents everything from happening at once.” - John Wheeler_), but that this is **static** (_ie._ there is no “now”, all configurations of the universe from the Big Bang to the Big Crunch simply **exist** ). In this way, the time axis is not _eliminated_, it is simply treated like another dimension of space such that, say, last Tuesday, “today”, and next Tuesday are different _places_ in the universe, and next Tuesdays events exist in precisely the same way as last Tuesday’s: “today” can simply have no _knowledge_ of them.

I perfectly understand the concept of a time axis, but I don’t necissarily see that being able to plot events in time means that the concept of time itself is somehow different.  
Or, I’ll put it this way, for me, there’s two possibilities.  
One, everything that ever has or will exist, is, already, in existance, and our moving in time is like a film from a projector. All the frames exist, but they get played one by one.  
The other possibility, is that time is continually being created, so, in effect, there is no future, only the present and the past.

> [@](#):
>
> Yep. We happen to live in ‘time’, whatever it is. We happen to live on Earth. When you ask “is there a beginning or end of time?”, how might one answer the question “is there a beginning or end of the sphere called Earth?”.

After posting the OP, I regretted using the term “end of time” because I personally believe in eternity, and eternity, of course, has no ending.

---

<div class="post-metadata">

**Author:** ![Liberal](https://avatars.discourse-cdn.com/v4/letter/l/848f3c/32.png) [@Liberal](https://boards.straightdope.com/u/Liberal)\
**Post date:** [January 13, 2005, 11:26am UTC](https://boards.straightdope.com/t/if-time-is-an-illusion/284351/15 "2005-01-13T11:26:03Z")

</div>

> [@SentientMeat](#):
>
> Not quite _so_ abtract, I would suggest: everything must still be _consistent_ with General Relativity and Quantum Mechanics, and hypotheses like [inflation](http://nedwww.ipac.caltech.edu/level5/Guth/Guth3.html) (coincidentally from the current GQ, presumably soon to be GD thread) **do** have observable consequences which give us confidence that we are not making it up as we go along from whole cloth.

Yes, but that doesn’t make them scientific. Freud, too, found confirmation for his theories in the observable consquences of practically everyone he met. So did his nemesis, Adler, for his opposing theories. Every newspaper headline confirmed the theories of Marx. And of the capitalist, Keynes, as well. The very definition of pseudo-science is that it takes no explanatory risk.

> [@](#):
>
> Why can’t I juggle -3 oranges?

Inasmuch as you gave me a term that is a function of time being less than zero and then set that function equal to another in which time equals exactly zero, I’m afraid you’re going to have to do better than that.

> [@](#):
>
> A useful analogy is [supergravity](http://en.wikipedia.org/wiki/Supergravity) (or, further, [M](http://en.wikipedia.org/wiki/M_theory) Theory), whereby more dimensions than “our” simple 3 of space and one of time are posited in order to _explain_ what we see in “ours”. If such a theory makes staggeringly accurate and non-circular predictions about what we _do_ see, it would be as useful an explanatory entity as Einstein’s General Relativity. Hence the “other timelines” model be _tested_ even though those timelines might not necessarily be directly tested _for_. However, the model always comes _before_ the possible testable consequences: we are already forced to spend billions of dollars building enormous synchrotrons to actually _test_ some models in physics. If our physics slips from the grasp of our engineering, we could still have confidence in its _consistency_ with well-tested theories.

I disagree. A theory isn’t useful just because it explains things. Heck, I could say that gravity is the arm-strength of angels holding the world together. That would explain everything from moons orbiting to apples falling. But if mere analytical symbologies, like M theory, may be extrapolated into reality simply because they are formulated into wiffs, then how can you deny the existence of God, which is analytically provable?

> [@](#):
>
> I said _more_ accurate than other terms. Remove the inverted commas if you like - I thought they might be useful in diversting ourselves of this thing called time, or at least exploring its nature.

Well, I don’t mind exploring the nature of time. In fact, I quite like it. I have many opinions on it. I just wanted to separate any existential discussion from an empirical one.

> [@](#):
>
> My hugely oversimplified equation represented the idea that the configuration of the universe at t=0 is precisely the same as that for any other value of t less than 0 because the function is _undefined_ for t less than 0, just as North is undefined for \<0[sup]o[/sup] latitude. That does not mean that the universe is carrying on doing all these unobservable undefined things for t\<0 anymore than there is a mysterious Land of UltraNorth at -3 degrees latitude. Timelessness is identical to an infinite amount of time without _change_. I argue that it is far more intellectually graspable not to simply rattle off that “t\<0 is undefined” (which is nevertheless accurate) but to consider the state at t=0 to be identical to all times between -infinity and 0.

I can understand how a function may be undefined when t _equals_ 0, where t is a denominator. But I don’t understand why a function with a negative t would ever be undefined unless the result of a t-calculation gives +/- infinity — in which case, a positive t would be just as undefined.

---

<div class="post-metadata">

**Author:** ![Liberal](https://avatars.discourse-cdn.com/v4/letter/l/848f3c/32.png) [@Liberal](https://boards.straightdope.com/u/Liberal)\
**Post date:** [January 13, 2005, 12:02pm UTC](https://boards.straightdope.com/t/if-time-is-an-illusion/284351/16 "2005-01-13T12:02:17Z")

</div>

> [@SentientMeat](#):
>
> Actually, perhaps my response to this question above was a little glib - I’ll try again.
> 
> Let us look at why the grumpy old [steady-state](http://en.wikipedia.org/wiki/Steady_state)-believing Yorkshireman Fred Hoyle coined the term of abuse “Big Bang” in the first place. Hubble’s obsevation of receding galaxies and the subsequent discovery of the [cosmic microwave background](http://en.wikipedia.org/wiki/CMB) show that the universe is undeniably **expanding**. So, as we rewind the tape further and further back, we get to the point where the universe is incredibly small, perhaps _infinitely_ small, at or near t=0.
> 
> Now, time and space are related according to Einstein’s Relativity. We are so used to thinking that “time goes on” that we struggle to divest ourselves of the notion. However, what can accurately be described as timelessness _does_ occur under Special Relativity (a photon’s frame of reference) and General Relativity (within the event horizon of a black hole). Is there any reason it _could not_ describe the state of the universe at t=0?
> 
> **Lib** quite reasonably asks “What about t\<0?”. Think of the universe shrinking on that rewound tape - to go any further back would have us asking “What about when the size of the universe is **smaller than zero**?” This is a question that we simply do not ask, even though it is every bit as reasonable as “What about t\<0?”. Why is that?
> 
> It is because in our everyday lives we understand that things can’t be smaller than nothing. But our everyday lives are contingent on _change_, on _time_ - we simply can’t imagine that it might not “go on” indefinitely, since we have no experience of travelling at 300,000 km per second or sitting in a black hole.
> 
> So, to answer more thoroughly: t could only equal -1 seconds if the universe could shrink until it was -300,000 km wide. I’d suggest just pretending it was the same size at t=-1 as it was at t=0.

A thoughtful response, but my understanding is that the Special Theory of Relativity is derived from two axioms: (1) physical law is the same for all inertial reference frames, and (2) the speed of light in vaccuo is the same for all intertial reference frames. Therefore, if something is moving, and one observer is stationary while another is not, then the path of photons to the observer at rest will form a right angle with respect to the path of the thing in motion. That means that the path of photons to the other observer will form an hypotenuse. If we call the path to the stationary observer CT, and the path to the moving observer CT’, and the distance travelled by the moving object VT, we can just apply the Pythagorean Theorem, (CT)[sup]2[/sup] = (VT)[sup]2[/sup] + (CT’)[sup]2[/sup], and solve for T: T = ( 1 - (V/C)2 )-1/2T’. All this really says about time is that T’ must always be greater than T; that is, the time interval for the moving observer must always be greater than the time interval for the stationary observer. I don’t think that a negative T would be a problem except in a world where diagonal motion relative to two perpindicular axes is impossible. In fact, I don’t see why a spacetime model cannot be created in which negative time represents the past, zero time the present, and positive time the future. It could be conically shaped with CT as the locus. There is no reason for t=0 to be “timelessness”.

---

<div class="post-metadata">

**Author:** ![SentientMeat](https://avatars.discourse-cdn.com/v4/letter/s/43a26b/32.png) [@SentientMeat](https://boards.straightdope.com/u/SentientMeat)\
**Post date:** [January 13, 2005, 12:04pm UTC](https://boards.straightdope.com/t/if-time-is-an-illusion/284351/17 "2005-01-13T12:04:29Z")

</div>

> [@](#):
>
> A theory isn’t useful just because it explains things.

I said it was useful if it makes staggeringly accurate non-circular predictions about what we _do_ observe like, say, General Relativity’s explanation of perturbations in the periheleon of Mercury. Do your angels do the same?

> [@](#):
>
> But if mere analytical symbologies, like M theory, may be extrapolated into reality simply because they are formulated into wiffs, then how can you deny the existence of God, which is analytically provable?

M theory is a physical model currently under construction. We simply don’t yet know what consequences it might have in terms of observable predictions - maybe we’ll need a synchrotron the size of Brazil to observe the things it predicts. What physically observable predictions does the God hypothesis make?

> [@](#):
>
> I don’t understand why a function with a negative t would ever be undefined unless the result of a t-calculation gives +/- infinity —— in which case, a positive t would be just as undefined.

OK, try [these two](http://en.wikipedia.org/wiki/Time_dilation) equations. In the first case let v=c, _ie._ the velocity of the body is exactly equal to the speed of light. In the second case, let C[sub]0[/sub] = C[sub]h[/sub], _ie._ the object is exactly at the event horizon.

How much time passes for the object, while the rest of the universe experiences billions or trillions of years and ends (_eg._ in a Big Crunch)? Does the object not experience _timelessness_?

Now try v\*\*\>\*\*c, or C[sub]0[/sub]\<C[sub]h[/sub]. What _time_ do the objects experience in that case?

---

<div class="post-metadata">

**Author:** ![SentientMeat](https://avatars.discourse-cdn.com/v4/letter/s/43a26b/32.png) [@SentientMeat](https://boards.straightdope.com/u/SentientMeat)\
**Post date:** [January 13, 2005, 12:12pm UTC](https://boards.straightdope.com/t/if-time-is-an-illusion/284351/18 "2005-01-13T12:12:53Z")

</div>

> [@](#):
>
> There is no reason for t=0 to be “timelessness”.

Your analysis of Special Relativity is quite correct. But when the entire universe is the size of a pearl, or perhaps of **zero** size, it is _General_ Relativity to which we appeal, and it is inuitive to compare that state to the singularity in a black hole.

---

<div class="post-metadata">

**Author:** ![Liberal](https://avatars.discourse-cdn.com/v4/letter/l/848f3c/32.png) [@Liberal](https://boards.straightdope.com/u/Liberal)\
**Post date:** [January 13, 2005, 5:08pm UTC](https://boards.straightdope.com/t/if-time-is-an-illusion/284351/19 "2005-01-13T17:08:37Z")

</div>

> [@SentientMeat](#):
>
> I said it was useful if it makes staggeringly accurate non-circular predictions about what we _do_ observe like, say, General Relativity’s explanation of perturbations in the periheleon of Mercury. Do your angels do the same?

Well, no, but neither does M theory. It’s just equations that make no predictions. For that matter, neither does your theory about “lines of time” that are “attached” to the initial singularity. Whether there are equations for it, I don’t know. I haven’t expressed any problem with the scientificness of General Relativity.

> [@](#):
>
> M theory is a physical model currently under construction. We simply don’t yet know what consequences it might have in terms of observable predictions - maybe we’ll need a synchrotron the size of Brazil to observe the things it predicts.

What does it predict? Please see [this recent discussion](http://www.math.columbia.edu/~woit/blog/archives/000133.html) from Columbia University’s website.

“In recent years, as it has become clear that string theory can never be used to predict anything about the real world, string theorists have reacted to this state of affairs in various often bizarre ways. Tonight there’s a new review article by Steve Giddings about string theory which doesn’t even pretend that the theory will ever make a real prediction about anything… With the current anthropic nonsense exemplified by this review article, string theory has finally reached rock-bottom. It has given up any claims to being a legitimate science and has taken on the characteristics of a cult. It is long past time for those leaders of the field with any remaining scientific integrity to take a public stand that what is going on is not all right.”

I couldn’t agree more.

> [@](#):
>
> What physically observable predictions does the God hypothesis make?

Well, none, but that’s the point I’m making. Nothing is predicted about time from relativity, except that it varies according to the circumstances of the observer. There’s nothing about any timelessness or eternity or original singularity.

> [@](#):
>
> OK, try [these two](http://en.wikipedia.org/wiki/Time_dilation) equations. In the first case let v=c, _ie._ the velocity of the body is exactly equal to the speed of light. In the second case, let C[sub]0[/sub] = C[sub]h[/sub], _ie._ the object is exactly at the event horizon.
> 
> How much time passes for the object, while the rest of the universe experiences billions or trillions of years and ends (_eg._ in a Big Crunch)? Does the object not experience _timelessness_?
> 
> Now try v\*\*\>\*\*c, or C[sub]0[/sub]\<C[sub]h[/sub]. What _time_ do the objects experience in that case?

Woah, Nellie! Those are equations of relativity — that is, one observer relative to another. Your prior comments were not about differences in observation, but about the universe as a singularity being timeless. If the universe is a singularity, then time dilation equations are rendered moot. There is not more than one thing, let alone more than one observer. Singularities are undefined equations that are like what you’re describing — i.e., v = c, and C0 = Ch. I don’t feel comfortable calling that “timelessness”. Is it “distancelessness” when you travel 1 mile in no time? I don’t even know what that means.

---

<div class="post-metadata">

**Author:** ![Liberal](https://avatars.discourse-cdn.com/v4/letter/l/848f3c/32.png) [@Liberal](https://boards.straightdope.com/u/Liberal)\
**Post date:** [January 13, 2005, 5:15pm UTC](https://boards.straightdope.com/t/if-time-is-an-illusion/284351/20 "2005-01-13T17:15:07Z")

</div>

> [@SentientMeat](#):
>
> Your analysis of Special Relativity is quite correct. But when the entire universe is the size of a pearl, or perhaps of **zero** size, it is _General_ Relativity to which we appeal, and it is inuitive to compare that state to the singularity in a black hole.

No, I’m afraid not. The whole brouhaha about a Theory of Everything in general, and string theory in particular, is that General Relativity does _not_ hold in the circumstance you describe. And the equations break down completely at zero. That’s why the search for the Holy Grail is on at all. Something is needed (and nothing exists) to explain the physics of the nascent universe.

[Next page](https://boards.straightdope.com/t/if-time-is-an-illusion/284351.md?page=2)