Is it possible that a finite amount of space in the universe exists without time? Namely, that it is possible for us to find an element of space that has no time (everything happened at one point and it does not change)?
Asked
Active
Viewed 946 times
4
-
Time is that which the clock shows. Can you exist without there being clocks? Nope. – CuriousOne Mar 28 '16 at 07:01
-
4@CuriousOne, I don't think he is asking if a person can exist without there being clocks, but can a small element of the universe exist without there being clocks? Perhaps a small bit of empty space, or the centre of a black hole? – Kenshin Mar 28 '16 at 07:04
-
@Mew: "Existence" without observation is not a scientific question. If you want to make "it" a scientific question, then "it" has to be observable, hence there is always a clock around. – CuriousOne Mar 28 '16 at 07:07
-
1@CuriousOne, so it is not scientific to ask whether or not empty space exists if there is no observers there to interact with it? I guess this question belongs in philosophy then. – Kenshin Mar 28 '16 at 07:08
-
2@Mew: My standard answer to that is that I will consider the physical properties of "nothing", as soon as someone manages to send me five lbs. of "nothing" by mail. Until then the notion of "empty space" is scientifically, forgive the pun, completely vacuous and so is the question if a falling tree makes a sound when there is nobody around to hear it. Science is operatively extremely well defined and none of these naive philosophical ideas fit into that definition. – CuriousOne Mar 28 '16 at 07:11
-
The phrase "finite amount of space that exists without time" is just meaningless in physics. What exactly do you mean? – ACuriousMind Mar 28 '16 at 11:48
3 Answers
5
In the relativistic paradigm, space is not an intrisic substance. The distinction between space and time depends on the reference frame you use to describe it. The properly existent substance, independent from the way one describes it, is simultaneously space and time and, in fact, is called spacetime. So, the answer is NO.
Valter Moretti
- 71,578
-
1Spacetime is not physical, either. The physical vacuum is physical and spacetime is simply a parametrization of the physical vacuum which, at the end of the day, seems to cause a lot of headaches. The sooner we learn to do without it, the better. – CuriousOne Mar 28 '16 at 08:24
-
1Your physical vacuum is a notion much more metaphysical and vague than the idea of spacetime itself. – Valter Moretti Mar 28 '16 at 08:34
-
The physical vacuum is that which causes matter and ultimately it's the physical vacuum that also gives rise to spacetime, we just don't know how, yet. – CuriousOne Mar 28 '16 at 08:48
-
Metaphysical squabbles aside (don't get me wrong, I love metaphysics), there IS a solution of the Einstein field equations that comes very close to having a space-like only region, namely, the maximally extended Schwarzschild solution. Here there is a coordinate frame in which we observe a bridge between two parallel universes, but this "bridge" only exists in space, but not in time. It has no duration; and no particle can cross it. – Andrea Mar 28 '16 at 20:13
-
You are referring to the bifurcation surface of a bifurcate Killing horizon. Yes it is spacelike, but it is embedded in the spacetime and has causal future and past. Every 2D flat spacelike surface in Minkowki space has the same properties as it is the bifurcation surface of a corresponding boost Killing vector field and it separates a pair of causally separated wedges. There is no problem with that. – Valter Moretti Mar 28 '16 at 22:04
-
(I like good metaphysics, theoretical physics relies upon a specialised form of it :)) – Valter Moretti Mar 28 '16 at 22:07
2
Yes, space exists without time everywhere, where no event is taking place. But we can not observe it in such a state. The moment (yes, the moment) we observe it, time comes into existence. We have to pick a moment to observe it, and that moment is time.
kpv
- 4,509
-
Are you saying that time doesn't exist if no observation is occurring? That explains the saying "A watched kettle never boils"... – Bohemian Mar 28 '16 at 10:39
-
-
-2
Time is the rate of change of space. If there is no change there is no time.
-
This does not provide an answer to the question. Once you have sufficient reputation you will be able to comment on any post; instead, provide answers that don't require clarification from the asker. - From Review – Jon Custer Mar 28 '16 at 13:20
-
@JonCuster: It is an answer; it's just an incorrect one. – Lightness Races in Orbit Mar 28 '16 at 13:50
-
@BarryTheHatchet - somewhat philosophical, but is an 'answer' that is incorrect actually an answer? – Jon Custer Mar 28 '16 at 13:54
-
2@JonCuster: Yes. On Stack Exchange, an answer that you personally believe to be incorrect may be denoted by a downvote. The "not an answer" flag should only be used for something that does not attempt to answer the question, such as a follow-up question or a "thanks" message. (If nothing else, imagine if flags instead of votes were used to express dissatisfaction with a post. Suddenly votes have no meaning and the entire democratic way of denoting post quality breaks down. Now it's just down to one guy who declares an answer incorrect and flags it for deletion? No!) – Lightness Races in Orbit Mar 28 '16 at 13:55
-
The unit of rate of change of space would be events per second. If that's also what time is then event's are in units of seconds squared? – candied_orange Mar 28 '16 at 13:58
-
@BarryTheHatchet - also note that the review queue offers up only a few canned comments. So, it was put up for a close vote, making that comment different from a regular comment. – Jon Custer Mar 28 '16 at 17:20
-
1@JonCuster: There is also a "custom comment" field that you could have used. No canned comments being applicable does not mean you should use them anyway! Quite the opposite. :) – Lightness Races in Orbit Mar 28 '16 at 17:23
-