[quote=cheeze]No. It doesn't. The truth table for implication is: A B A->B T T T T F F F T T F F T[/quote]This is not wrong, so much as irrelevant. If A is false, you know nothing about B, and if A does not imply B, the whole exercise is pointless. Time travel being physically impossible, would imply we do not have time travel technology. But this isn't what I said either, I implied only that we do not currently have time travel technology, and said nothing about the physical possibility of time travel.

Quote from cheeze

No. It doesn't. The truth table for implication is:

A B A->B
T T T
T F F
F T T
F F T

This is not wrong, so much as irrelevant. If A is false, you know nothing about B, and if A does not imply B, the whole exercise is pointless.

Time travel being physically impossible, would imply we do not have time travel technology.
But this isn't what I said either, I implied only that we do not currently have time travel technology, and said nothing about the physical possibility of time travel.

The implication I made in my first statement is that if we achieve the technology to go back in time, we will know enough about the physics of said technology, to know if the grandfather paradox is relevant.

The implication I made in my first statement is that if we achieve the technology to go back in time, we will know enough about the physics of said technology, to know if the grandfather paradox is relevant.

[quote]If A is false, you know nothing about B, and if A does not imply B, the whole exercise is pointless.[/quote] If A is false, it doesn't matter if A implies B or not, B can be anything. It certainly is not pointless as it allows things to be vacuously true. Also known as proof by contradiction. But of course, [i]you[/i] already knew this.

Quote

If A is false, you know nothing about B, and if A does not imply B, the whole exercise is pointless.

If A is false, it doesn't matter if A implies B or not, B can be anything. It certainly is not pointless as it allows things to be vacuously true. Also known as proof by contradiction. But of course, you already knew this.

That has no relevance to anything in this thread, which makes it pointless.

That has no relevance to anything in this thread, which makes it pointless.

The topic itself is worthless because time travel is not yet possible, as you said. So I made it worthwhile by explaining how implication works. Hopefully we learned something today.

The topic itself is worthless because time travel is not yet possible, as you said. So I made it worthwhile by explaining how implication works. Hopefully we learned something today.

Next time, let the topic die, and post a new thread.

Next time, let the topic die, and post a new thread.

timetravel is an utopia? if timetravel will be possible, that would become the most dangerous weapon in a humans hand, if you travel back in your own timeline. which technic would be more elevated than timetravel? timetravel is the last thing we could do, or?

timetravel is an utopia?

if timetravel will be possible, that would become the most dangerous weapon in a humans hand, if you travel back in your own timeline.
which technic would be more elevated than timetravel? timetravel is the last thing we could do, or?

Just a note: If you went back 5 minutes... wouldn't you see yourself 5 minutes earlier? This is why I believe time travel is impossible, because it adds to such complications.

Just a note: If you went back 5 minutes... wouldn't you see yourself 5 minutes earlier? This is why I believe time travel is impossible, because it adds to such complications.

Calculus is also impossible, so is Shakespeare. From hear on, You is the real you. Any other you is a result of time travel. You would see yourself from five minutes ago. That you could possibly end up traveling backward in time, with the knowledge of seeing himself five minutes ago. I think the overriding question is, if You traveled back five minutes and then that you did the same, would that you affect You? Or would it be as if his matter left the universe?

Calculus is also impossible, so is Shakespeare.

From hear on, You is the real you. Any other you is a result of time travel.
You would see yourself from five minutes ago. That you could possibly end up traveling backward in time, with the knowledge of seeing himself five minutes ago.

I think the overriding question is, if You traveled back five minutes and then that you did the same, would that you affect You? Or would it be as if his matter left the universe?

Even if time travel existed, there would be no such thing as a grandfather paradox.

Even if time travel existed, there would be no such thing as a grandfather paradox.

After some thought. Time travel is IMPOSSIBLE. Not only is it impossible, but the past doesn't even exist. All that exists is the here and now. Time is simply a man-made idea. AND is not a dimensional law. Time is something recorded and made by man. Time in fact isn't linear. Rather it is a point.

After some thought. Time travel is IMPOSSIBLE. Not only is it impossible, but the past doesn't even exist. All that exists is the here and now. Time is simply a man-made idea. AND is not a dimensional law. Time is something recorded and made by man. Time in fact isn't linear. Rather it is a point.

Interesting Akar, the presentist view. Oh no, I don't know what to do. You've presented me with a classic hard to fight viewpoint. Oh noes!!!! Wikipedia, help! [QUOTE=Wikipedia]the relativity of simultaneity in modern physics is generally understood to cast serious doubt on presentism and to favor the view known as four dimensionalism (closely related to the idea of block time) in which past, present and future events all coexist in a single spacetime.[/QUOTE] Sounds good to me. The point is, time does in fact exist. Sort of. If you go for general relativity, time really can be shown to exist. Also, most physical stuff (like string theory!!! Yay string theory!) depends on time existing. That isn't to say that time travel is impossible. If string theory were true, it would sort of prove once and for all that time travel is not possible, I think. Edit: Quotes yay! [QUOTE]This means that if observer A sends a signal to observer B which moves FTL (faster than light) in A's frame but backwards in time in B's frame, and then B sends a reply which moves FTL in B's frame but backwards in time in A's frame, it could work out that A receives the reply before sending the original signal, a clear violation of causality in every frame.[/QUOTE] I love it.

Interesting Akar, the presentist view. Oh no, I don't know what to do. You've presented me with a classic hard to fight viewpoint. Oh noes!!!!
Wikipedia, help!

Quote from Wikipedia

the relativity of simultaneity in modern physics is generally understood to cast serious doubt on presentism and to favor the view known as four dimensionalism (closely related to the idea of block time) in which past, present and future events all coexist in a single spacetime.

Sounds good to me. The point is, time does in fact exist. Sort of. If you go for general relativity, time really can be shown to exist. Also, most physical stuff (like string theory!!! Yay string theory!) depends on time existing.

That isn't to say that time travel is impossible. If string theory were true, it would sort of prove once and for all that time travel is not possible, I think.


Edit: Quotes yay!

Quote

This means that if observer A sends a signal to observer B which moves FTL (faster than light) in A's frame but backwards in time in B's frame, and then B sends a reply which moves FTL in B's frame but backwards in time in A's frame, it could work out that A receives the reply before sending the original signal, a clear violation of causality in every frame.

I love it.

Time travel can't work in the way "send my body to the past", since this would remove energy from the current point of time and insert it into another, which obviously violates some fancy little law. So, if you are thinking of time travel in this way, don't apply any of our currently widely accepted physical models. I wonder in what kind of world you live in when you believe in this kind of time travel... There are other conceptions of "time travel", for example reverting the whole universe to an earlier state. Too bad you might not even exist in that point of time... In this concept, you can even call the flow of time "time travel". Add determinism to that and it gets kinda loopy... Anyways, this whole thread is lulz.

Time travel can't work in the way "send my body to the past", since this would remove energy from the current point of time and insert it into another, which obviously violates some fancy little law. So, if you are thinking of time travel in this way, don't apply any of our currently widely accepted physical models. I wonder in what kind of world you live in when you believe in this kind of time travel...

There are other conceptions of "time travel", for example reverting the whole universe to an earlier state. Too bad you might not even exist in that point of time... In this concept, you can even call the flow of time "time travel".
Add determinism to that and it gets kinda loopy...

Anyways, this whole thread is lulz.

[QUOTE]Why so? Because you don't like people smarter than you, proving that they are? Sorry had to say it.......... Cause Cheeze just PIZZOWNED you. Anywho, I believe any discussion further on is infaliable due to Cheeze's pwn of AntiSleep, and the thread.[/QUOTE] No, cheeze just went completely off-topic and turned antisleep's words into something he never said, nor implied, more than once. Sigh.

Quote

Why so? Because you don't like people smarter than you, proving that they are?


Sorry had to say it.......... Cause Cheeze just PIZZOWNED you.


Anywho, I believe any discussion further on is infaliable due to Cheeze's pwn of AntiSleep, and the thread.

No, cheeze just went completely off-topic and turned antisleep's words into something he never said, nor implied, more than once. Sigh.

I agree with spinessheath, time travel has to be impossible because it would imbalance E = mc²

I agree with spinessheath, time travel has to be impossible because it would imbalance E = mc²

[quote=Dapperdan][QUOTE]Why so? Because you don't like people smarter than you, proving that they are? Sorry had to say it.......... Cause Cheeze just PIZZOWNED you. Anywho, I believe any discussion further on is infaliable due to Cheeze's pwn of AntiSleep, and the thread.[/QUOTE] No, cheeze just went completely off-topic and turned antisleep's words into something he never said, nor implied, more than once. Sigh.[/quote] Sorry, but no. Oh, if only DrunkenWrestler still was here, :lol:

Quote from Dapperdan

Quote

Why so? Because you don't like people smarter than you, proving that they are?


Sorry had to say it.......... Cause Cheeze just PIZZOWNED you.


Anywho, I believe any discussion further on is infaliable due to Cheeze's pwn of AntiSleep, and the thread.

No, cheeze just went completely off-topic and turned antisleep's words into something he never said, nor implied, more than once. Sigh.

Sorry, but no.


Oh, if only DrunkenWrestler still was here,

[quote=Akar]I agree with spinessheath, time travel has to be impossible because it would imbalance E = mc²[/quote] Actually, the law it violates is the fundamental law of thermodynamics. That is, no mass or energy can ever be added to the universe. Of course, that law is based on our understanding of what we can do. E=MC² does not describe all the matter and energy in the universe. It's basically a proportionality description. For example, a 150 pound man is roughly equivalent to 610,000,000,000,000 Joules That's enough energy to deliver a Giga-Watt of power for about a week, or a Mega-Watt for 20 years. Also, that law of thermodynamics is itself based on physical observations by us humans. If time travel (and please don't try to redefine time travel and declare yourself victor of the discussion) were indeed possible, that law may have to be rebalanced, just as the laws of physics were redefined for atomic stuff. A law based on an observation in one field cannot be expanded to another without further observation.

Quote from Akar

I agree with spinessheath, time travel has to be impossible because it would imbalance E = mc²

Actually, the law it violates is the fundamental law of thermodynamics. That is, no mass or energy can ever be added to the universe. Of course, that law is based on our understanding of what we can do.
E=MC² does not describe all the matter and energy in the universe. It's basically a proportionality description. For example, a 150 pound man is roughly equivalent to 610,000,000,000,000 Joules
That's enough energy to deliver a Giga-Watt of power for about a week, or a Mega-Watt for 20 years.

Also, that law of thermodynamics is itself based on physical observations by us humans. If time travel (and please don't try to redefine time travel and declare yourself victor of the discussion) were indeed possible, that law may have to be rebalanced, just as the laws of physics were redefined for atomic stuff. A law based on an observation in one field cannot be expanded to another without further observation.

[quote=frazz][quote=Akar]I agree with spinessheath, time travel has to be impossible because it would imbalance E = mc²[/quote] Actually, the law it violates is the fundamental law of thermodynamics. That is, no mass or energy can ever be added to the universe. Of course, that law is based on our understanding of what we can do. E=MC² does not describe all the matter and energy in the universe. It's basically a proportionality description. For example, a 150 pound man is roughly equivalent to 610,000,000,000,000 Joules That's enough energy to deliver a Giga-Watt of power for about a week, or a Mega-Watt for 20 years. Also, that law of thermodynamics is itself based on physical observations by us humans. If time travel (and please don't try to redefine time travel and declare yourself victor of the discussion) were indeed possible, that law may have to be rebalanced, just as the laws of physics were redefined for atomic stuff. A law based on an observation in one field cannot be expanded to another without further observation.[/quote] Your calculation is wrong, it is 6.1*10^18 J, not 6.1*10^14(as you said it was), meaning it would supply a megawatt for 4.6 million years, or a gigawatt for 4.6 thousand years.

Quote from frazz

Quote from Akar

I agree with spinessheath, time travel has to be impossible because it would imbalance E = mc²

Actually, the law it violates is the fundamental law of thermodynamics. That is, no mass or energy can ever be added to the universe. Of course, that law is based on our understanding of what we can do.
E=MC² does not describe all the matter and energy in the universe. It's basically a proportionality description. For example, a 150 pound man is roughly equivalent to 610,000,000,000,000 Joules
That's enough energy to deliver a Giga-Watt of power for about a week, or a Mega-Watt for 20 years.

Also, that law of thermodynamics is itself based on physical observations by us humans. If time travel (and please don't try to redefine time travel and declare yourself victor of the discussion) were indeed possible, that law may have to be rebalanced, just as the laws of physics were redefined for atomic stuff. A law based on an observation in one field cannot be expanded to another without further observation.

Your calculation is wrong, it is 6.1*10^18 J, not 6.1*10^14(as you said it was), meaning it would supply a megawatt for 4.6 million years, or a gigawatt for 4.6 thousand years.

So who's going off topic now? I guess I am. :(

So who's going off topic now? I guess I am.

I would like to ask... How do we know, beyond intuition and having not seen an example of it being broken, that the law of conservation ( or any other law, for that matter ) , is true? Or there are plenty of fancy ways to go about holding it - by 'linking' ourselves with another time, our current universe is no longer a closed system of itself, and so an equal amount of matter/energy would have to swap places with you in order for you to move back. Although I stand by the idea that until we have atleast some very basic, fundamental idea as to how such a technology could work, there's not really much we can say about what result is more likely than what, anyways, making the whole topic pointless. It's like speculating on what's on the inside of a box of infinite size, when there's no information coming from it. You can guess, sure, but none of the guesses are really based on anything more than, 'it's inside the infinite box.'

I would like to ask...
How do we know, beyond intuition and having not seen an example of it being broken, that the law of conservation ( or any other law, for that matter ) , is true? Or there are plenty of fancy ways to go about holding it - by 'linking' ourselves with another time, our current universe is no longer a closed system of itself, and so an equal amount of matter/energy would have to swap places with you in order for you to move back.

Although I stand by the idea that until we have atleast some very basic, fundamental idea as to how such a technology could work, there's not really much we can say about what result is more likely than what, anyways, making the whole topic pointless.
It's like speculating on what's on the inside of a box of infinite size, when there's no information coming from it. You can guess, sure, but none of the guesses are really based on anything more than, 'it's inside the infinite box.'