Time Machine will not be invented

[Ash Small]

But that's just the point though isn't it. You can argue what you like, but there is no evidence either way. For every argument you can provide against time travel, there is a counter-argument which circumvents that issue and allows it.

The OP made a statement and this thread has been a discussion of this statement (or should have been). We aren't here to debate is or isn't it possible. We are here to either explain a) why the OP is correct or b) why it is incorrect based on current hypothesis for/against time travel. Not to debate whether or not it is possible - this cannot happen for the reason given above.

Now you may not like what I've said above, but unless you have some revolutionary new evidence which shows it is not possible, you're arguments are equally as speculative as those in favour of time travel.

Jared, if I argue that there is no evidence that a time machine will be invented in the future because no-one has traveled back from the future and that if a time machine were to be invented in the future then there would be evidence of it because people would have traveled back from the future, therefore we know that a time machine will never be invented, would you accept this conclusion?

 

[DaveC426913]

Dave, are you saying that, unless some-one proves otherwise, time travel IS possible,

No, I am saying that, unless someone proves otherwise, time travel (or anything else) might be possible. That is not a claim, it is simply a statement.

Contrarily, saying that time travel is not possible is a claim, and needs to have a case made for it.

I'd argue that time travel is not possible unless someone proves otherwise.

Fine. Back up your claim. Unless you make the case that it can't be done, the default state is that it might be i.e. we just don't know.

See how the two are not equivalent?

Sally has a marble bag with an unknown number of marbles in it.
Dave claims it may contain marbles.
Ash claims there are no marbles in it.
Dave asks Ash to show how he's sure there are no marbles in it. Ash must make his case. If ash does not show how he's sure, then Dave is correct by default - there might be marbles in it.

Dave has no such obligation to demonstrate that there might be marbles in the bag. It is simply a statement of fact until and unless shown to be otherwise.

("Might" is a very safe and easily defensible stance. It is also noncommital and not very productive for a lively discussion. )

 

[JaredJames]

Jared, if I argue that there is no evidence that a time machine will be invented in the future because no-one has traveled back from the future and that if a time machine were to be invented in the future then there would be evidence of it because people would have traveled back from the future, therefore we know that a time machine will never be invented, would you accept this conclusion?

No. This is purely speculative and not backed up by evidence. We can counter this with:

You're forgetting the whole "you can't travel back any further than when the time machine is activated" hypothesis. We don't have a time machine yet, therefore no one could have come back to tell us it's possible.

Like I said, for every argument against, there's a counter for it. This isn't a debatable topic unless you have some new evidence for/against it that strongly backs up your statement of "it's not possible".

I personally don't care one way or another regarding time travel. If I had to choose it would be 'might be possible' as per Daves post above.

 

[Ash Small]

No, I am saying that, unless someone proves otherwise, time travel (or anything else) might be possible. That is not a claim, it is simply a statement.

Contrarily, saying that time travel is not possible is a claim, and needs to have a case made for it.


Fine. Back up your claim. Unless you make the case that it can't be done, the default state is that it might be i.e. we just don't know.

See how the two are not equivalent?

Sally has a marble bag with an unknown number of marbles in it.
Dave claims it may contain marbles.
Ash claims there are no marbles in it.
Dave asks Ash to show how he's sure there are no marbles in it. Ash must make his case. If ash does not show how he's sure, then Dave is correct by default - there might be marbles in it.

Dave has no such obligation to demonstrate that there might be marbles in the bag. It is simply a statement of fact until and unless shown to be otherwise.

("Might" is a very safe and easily defensible stance. It is also noncommital and not very productive for a lively discussion. )

Dave, if we look in the bag and can't see any marbles we can conclude that there are no marbles in the bag.

Similarly, if we look for evidence that people have traveled back from the future, but can't find any, we can conclude that a time machine will never be invented.

 

[DaveC426913]

Jared, if I argue that there is no evidence that a time machine will be invented in the future because no-one has traveled back from the future and that if a time machine were to be invented in the future then there would be evidence of it because people would have traveled back from the future, therefore we know that a time machine will never be invented, would you accept this conclusion?

I too refute this conclusion.

I agree there we can speculate about why we see no evidence of time travel on our public roads, but that still leads to 'maybe's.

Would a native of Papua New Guinea be able to successfully argue that 'man cannot fly in heavier-than air machines' based on his observation that he's never seen one?

 

[JaredJames]

Similarly, if we look for evidence that people have traveled back from the future, but can't find any, we can conclude that a time machine will never be invented.

Again, see my previous post regarding a potential 'why' this isn't a definite solution to the time travel hypothesis.

 

[JaredJames]

I agree there we can speculate about why we see no evidence of time travel on our public roads, but that still leads to 'maybe's.

Exactly. It's all speculation and thanks to the countless arguments for and against time travel you end up in a loop where there is always one 'out doing' another and allowing it to occur / not occur. All you end up with is maybe it is or maybe it isn't.

 

[DaveC426913]

Exactly. It's all speculation and thanks to the countless arguments for and against time travel you end up in a loop where there is always one 'out doing' another and allowing it to occur / not occur.

Well, it's not all loosey-goosey useless. It is possible that there's a valid argument against time travel but that we just haven't found it yet. Not every avenue ends inevitably in a 'maybe'.

For example, if Ash's PEP argument had been valid, that would have shown that, according to our current understanding of physics, it can't be done (at least until someone found a loophole in the PEP argument).

So there is still value in discussing it.

 

[Ash Small]

I too refute this conclusion.

I agree there we can speculate about why we see no evidence of time travel on our public roads, but that still leads to 'maybe's.

Would a native of Papua New Guinea be able to successfully argue that 'man cannot fly in heavier-than air machines' based on his observation that he's never seen one?

Dave, by saying 'might' you are, by default, arguing that 'it is POSSIBLE that a time machine WILL be invented', yet you don't give any example of accepted scientific theory to back this claim up.

All the evidence we have indicates that the OP was correct in stating 'a time machine will never be invented'.

With all due respect, you are indicating that you are as ignorant as your hypothetical friend from Papua New Guinea.

(The above phrase is used to make a point, and is in no way meant to be taken personally, Dave.)

 

[JaredJames]

Dave, by saying 'might' you are, by default, arguing that 'it is POSSIBLE that a time machine WILL be invented', yet you don't give any example of accepted scientific theory to back this claim up.

All the evidence we have indicates that the OP was correct in stating 'a time machine will never be invented'.

With all due respect, you are indicating that you are as ignorant as your hypothetical friend from Papua New Guinea.

(The above phrase is used to make a point, and is in no way meant to be taken personally, Dave.)

Might goes either way. Just because I think time travel might be invented, doesn't mean I believe it definitely is possible. What you are throwing in there is a red herring by implying that by accepting a possibility you are completely agreeing with it.

What evidence says it isn't possible? You haven't provided any. I really would like to see it. All I've heard so far is speculation on both sides.

 

[DaveC426913]

Dave, if we look in the bag and can't see any marbles we can conclude that there are no marbles in the bag.

We cannot "look in the bag" when it comes to the invention of time travel. That is the future. We cannot see the future.

Similarly, if we look for evidence that people have traveled back from the future, but can't find any, we can conclude that a time machine will never be invented.

Absence of evidence is not evidence of absence.

Like I said: is the native of Papua New Guinea correct when he says man cannot fly in heavier-than-air craft?

 

[DaveC426913]

Dave, by saying 'might' you are, by default, arguing that 'it is POSSIBLE that a time machine WILL be invented', yet you don't give any example of accepted scientific theory to back this claim up.

Don't need to.

All the evidence we have indicates that the OP was correct in stating 'a time machine will never be invented'.

We have zero evidence that it will never be invented.

Absence of evidence is not evidence of absence.

With all due respect, you are indicating that you are as ignorant as your hypothetical friend from Papua New Guinea.

Yes. We are all ignorant of what will or won't happen in the future. Or do you disagree?

 

[Ash Small]

Don't need to.


We have zero evidence that it will never be invented.

Absence of evidence is not evidence of absence.



Yes. We are all ignorant of what will or won't happen in the future. Or do you disagree?

Dave, once again I'm forced to concede that you are correct.

 

[JDługosz]

JD, I understood that the radius of a proton is around 0.8768 femtometers (0.8768 x 10^-15 m) and the radius of a hydrogen atom (proton + electron) is around 5.2917720859(36) × 10^−11 m.

This means an electron occupies around 50,000 times as much space as a proton (assuming my maths is correct).

I always understood the electron surrounds the proton as opposed to being 'in the same place', although it's obviously attracted to it. (I suppose it's [sic - "its"] C of G is in the same place, but that's not the same as 'being in the same place'.)

Actually, both extend to infinity, but one falls off faster than the other. Even considering a useful cut-off for "size", one the smaller one overlaps the larger one. It doesn't cut out a hole or anything.

Consider two electrons in the same ground state, but opposite spin. In the absence of a magnetic field, they will be identical in size and shape, have zero orbital angular momentum and spherical "shape", in the exact same place.

 

[Ash Small]

Actually, both extend to infinity, but one falls off faster than the other. Even considering a useful cut-off for "size", one the smaller one overlaps the larger one. It doesn't cut out a hole or anything.

Consider two electrons in the same ground state, but opposite spin. In the absence of a magnetic field, they will be identical in size and shape, have zero orbital angular momentum and spherical "shape", in the exact same place.

JD, I agree, The radiuses I was quoting were the 'accepted' ones.

There is a problem with my maths as well, the 50,000 I quoted is radius, not volume. I think I need to multiply by 4/3 pi r^3, or something.

While the two electrons you mention do occupy the same space, they do not occupy the same 'state', as they have opposite spin (just clarifying this point following my previous comments regarding PEP).

 

[DaveC426913]

Dave, once again I'm forced to concede that you are correct.

It's better this way. Saves a lot of time and heartache.

 

[Magnethos]

Almost 2 months without updating this thread...

Ok, I'm posting again because I saw some interesting information that could be useful to better understand (or not) the possibility of Time Travel. First of all, I think, we need to understand how to travel in the actual spacetime. Once we start to believe in a possible way to travel in the actual spacetime, then we can start speaking about traveling throught time.

Travel at a distance, teleportation, could be possible manipulating a finite amount of mass via electricity. To teleport something from point A to point B, the finite amount of mass needs to be de-materialized in A, and then materialized in B. For that pourpouse you need to understand about Transmutation.

First of all, we could answer to these questions...
1) What is matter?
2) How matter can be altered using electrical energy?

 

[berkeman]

This is silly. Thread locked pending cleanup.