Mr. Astrophysicist Posted February 21, 2015 Share Posted February 21, 2015 Introduction As we watch various science fiction shows, sitcoms, and as I could name on to infinite possible activities as stated, you've all heard the famous theory of time, or perhaps has been mentioned at least once in our lives: Time travel. Now, time travel is not as sophisticated as it looks or perhaps sound. Actually, it is pretty simple. While to some, traveling through time, or perhaps back to the past or into the future, is somewhat filled with paradoxes and might just knock you out, is very easy to get past and explain this. Speed of Light While some argue that travelling at the speed of light is an important essence to traveling through time, and others claim that its not even possible, not to be judging beliefs, but it is quite possible, given a limit of travelling back to the past, but traveling into the future is possible. If we could master a possibility to travel at the speed of light, we could actually slow down time; If you did, everything around you would age: But you wouldn't. If you were to do so, some theorises that if we were in a space shuttle or train on earth or perhaps space, and travelling at the speed of light for a year, we would emerge, a few hundreds, or tens of thousands of years from where we started. And while some may also state that travelling at the speed of light to enter wormholes that may warp to the past; while it is possible, is very hard. Be skeptical. Wormholes allow tiny particles and entering at the start of when one is created is hard, as the end may slam shut (who knows) and you could be trap in the infinite abyss. It is a theory, but risking it wouldn't help. I have done calculations, and 1 astronomical unit is 150,000,000 kilometres, and 1 wormhole is possibly 1 AU, and thus, light being the fastest thing in the entire infinite universe, possibly other substances of matter or other massless particles may be faster, it would 500 seconds average for us, travelling at the speed of light to past 1 Astronomical unit. Anyways, zooming into this example, the speed of light is 299,792,458 m/s. The distance of the sun and earth is 1 astronomical unit, and as the sun rises, you notice that earth doesn't automatically be filled with light, but actually, it would take roughly a few minutes for it to have light, (Disregarding the exception of the moon as well) as light would be travelling the astronomical unit. To be continued... Link to comment Share on other sites More sharing options...
tyme Posted February 21, 2015 Share Posted February 21, 2015 What you said is not traveling through time but altering times flow. Yes traveling at c will make time for you slower, but thats all it is, time going slower for you and faster around you. Link to comment Share on other sites More sharing options...
Mr. Astrophysicist Posted February 21, 2015 Author Share Posted February 21, 2015 What you said is not traveling through time but altering times flow. Yes traveling at c will make time for you slower, but thats all it is, time going slower for you and faster around you. Thanks for the information; But I already know that isn't actually time travel, I'm just stating the theories of light speed by some of our brilliant minds of our time. 1 Link to comment Share on other sites More sharing options...
swansont Posted February 21, 2015 Share Posted February 21, 2015 If we could master a possibility to travel at the speed of light, we could actually slow down time; If you did, everything around you would age: But you wouldn't. Experiments confirming relativity have shown that travel to c isn't required for this to happen. Time slows down for all relative motion (and also positions in a gravitational potential); the amount of that slowing increases as you approach c. Link to comment Share on other sites More sharing options...
Mr. Astrophysicist Posted February 21, 2015 Author Share Posted February 21, 2015 Experiments confirming relativity have shown that travel to c isn't required for this to happen. Time slows down for all relative motion (and also positions in a gravitational potential); the amount of that slowing increases as you approach c. Good point. The theory is disproven, but as to how we travel to the speed of light is quite possible, though some say it is impossible, and Einstein's limits should be followed. But what do you think of that. As notice that light gets scattered as it travels further. Would our atoms, particles and molecules scatter if we do so? I think so, and we need to reduce it somehow for us to gain that possibility. Thoughts? Link to comment Share on other sites More sharing options...
tyme Posted February 21, 2015 Share Posted February 21, 2015 (edited) Good point. The theory is disproven, but as to how we travel to the speed of light is quite possible, though some say it is impossible, and Einstein's limits should be followed. But what do you think of that. As notice that light gets scattered as it travels further. Would our atoms, particles and molecules scatter if we do so? I think so, and we need to reduce it somehow for us to gain that possibility. Thoughts? When traveling at c, an object's mass will become infinite. You would also need an infinite source of energy. I doubt Humans will find the infinite source of energy required to travel at c within the next half a millennia. So I'm calling time travel plausible for the moment. Edited February 21, 2015 by tyme Link to comment Share on other sites More sharing options...
Mr. Astrophysicist Posted February 21, 2015 Author Share Posted February 21, 2015 (edited) When traveling at c, an object's mass will become infinite. You would also need an infinite source of energy. I doubt Humans will find the infinite source of energy required to travel at c within the next half a millennia. So I'm calling time travel plausible for the moment. I highly doubt it. Infinity and all its theories doesn't apply to the speed of light, unless you're talking about its particles scattering and could be infinite as we go on, it doesn't really apply to its object's mass. It's mass would be zero/0, or just completely massless, as only massless particles could travel at the speed of light. While we're on this awesome intellectual topic, how old do you think I am? Based on my grammar, maturity, and knowledge. Edited February 21, 2015 by Jordyn Rahizel Link to comment Share on other sites More sharing options...
Strange Posted February 21, 2015 Share Posted February 21, 2015 how old do you think I am? Based on my grammar, maturity, and knowledge. I am going for about 13. Based on your level of knowledge and vivid imagination.... Link to comment Share on other sites More sharing options...
Mr. Astrophysicist Posted February 21, 2015 Author Share Posted February 21, 2015 I am going for about 13. Based on your level of knowledge and vivid imagination.... How the hell...? It was actually a very accurate guess. Yes, I am! I thought people would go for more due to my 'gift' or genius intellect they keep on saying xD Link to comment Share on other sites More sharing options...
Robittybob1 Posted February 21, 2015 Share Posted February 21, 2015 I highly doubt it. Infinity and all its theories doesn't apply to the speed of light, unless you're talking about its particles scattering and could be infinite as we go on, it doesn't really apply to its object's mass. It's mass would be zero/0, or just completely massless, as only massless particles could travel at the speed of light. While we're on this awesome intellectual topic, how old do you think I am? Based on my grammar, maturity, and knowledge. 73 - like Stephen Hawking Link to comment Share on other sites More sharing options...
Mr. Astrophysicist Posted February 21, 2015 Author Share Posted February 21, 2015 73 - like Stephen Hawking Haha, xD I'm not that old, I'm 13. A 'gifted' genius in physics as my peers, teachers and family say. The picture is a fine biography of Stephen Hawking; one of the persons that inspired me to pursue mathematics, astronomy, astrophysics, and physics. Link to comment Share on other sites More sharing options...
Robittybob1 Posted February 21, 2015 Share Posted February 21, 2015 Haha, xD I'm not that old, I'm 13. A 'gifted' genius in physics as my peers, teachers and family say. The picture is a fine biography of Stephen Hawking; one of the persons that inspired me to pursue mathematics, astronomy, astrophysics, and physics. I'm just a dummy ... what does xD mean? Link to comment Share on other sites More sharing options...
Mr. Astrophysicist Posted February 21, 2015 Author Share Posted February 21, 2015 I'm just a dummy ... what does xD mean? Just to quote it short, I'm not old. I'm 13. The picture is Stephen hawking. Link to comment Share on other sites More sharing options...
andrewcellini Posted February 21, 2015 Share Posted February 21, 2015 I'm just a dummy ... what does xD mean? xD is a "laughing really hard" kind of face. 1 Link to comment Share on other sites More sharing options...
Strange Posted February 21, 2015 Share Posted February 21, 2015 I'm just a dummy ... what does xD mean? LMGTFY: https://www.google.co.uk/search?q=what+does+xD+mean Link to comment Share on other sites More sharing options...
Robittybob1 Posted February 21, 2015 Share Posted February 21, 2015 Just to quote it short, I'm not old. I'm 13. The picture is Stephen hawking. I'm not that dumb! Link to comment Share on other sites More sharing options...
Mr. Astrophysicist Posted February 21, 2015 Author Share Posted February 21, 2015 I'm not that dumb! Ah, sorry for the misinterpretation. I thought you were using the text slang in the facial expression... xD Link to comment Share on other sites More sharing options...
Robittybob1 Posted February 21, 2015 Share Posted February 21, 2015 Ah, sorry for the misinterpretation. I thought you were using the text slang in the facial expression... xD I was asking what xD meant. I hadn't come across it before. I'm backward in time. Link to comment Share on other sites More sharing options...
swansont Posted February 21, 2015 Share Posted February 21, 2015 Good point. The theory is disproven, but as to how we travel to the speed of light is quite possible, though some say it is impossible, and Einstein's limits should be followed. But what do you think of that. As notice that light gets scattered as it travels further. Would our atoms, particles and molecules scatter if we do so? I think so, and we need to reduce it somehow for us to gain that possibility. Thoughts? What theory is disproven? Link to comment Share on other sites More sharing options...
Mr. Astrophysicist Posted February 22, 2015 Author Share Posted February 22, 2015 What theory is disproven? No, not this thread, it'd be pretty stupid to disprove my theory. The theory of "travelling at c, slows down time, but you wouldn't", is actually not disproven in my opinion. We haven't come to the extent of having superior technology to find that out. We'll leave that theory be for a couple years. -1 Link to comment Share on other sites More sharing options...
ajb Posted February 22, 2015 Share Posted February 22, 2015 Haha, xD I'm not that old, I'm 13. A 'gifted' genius in physics as my peers, teachers and family say. Well it is all relative. No, not this thread, it'd be pretty stupid to disprove my theory. You have not really presented a theory here. In physics a theory is a mathematical model that we can use to model nature. A theory is 'good' if it matches nature well enough for our purposes, or 'bad' if not. The theory of "travelling at c, slows down time, but you wouldn't", is actually not disproven in my opinion. So you will need to present some mathematical details on travelling at the speed of light (relative to what?) and how this effects the measurement of proper time. We haven't come to the extent of having superior technology to find that out. We'll leave that theory be for a couple years. Well, it is not just an issue to technology. The theory of special and general relativity tell us that (locally) a massive body cannot travel at a speed equal to or greater than the speed of light as measured by an inertial observer. In short, no-one can measure the speed of a body to be the speed of light. There are some 'get-outs' here. You can use the geometry of space-time to have motions that break the global speed of light, such as using a wormhole or a warp drive. Both of these could be used to create a time machine or a CTC (closed time-like curve) as we rather call them. The problem is that such devices seem to require 'exotic matter' such as matter with negative mass. It may be possible to use quantum effects to generate the necessary negative energy densities. However, so far all known time machines are sick. They suffer from real problems when quantum mechanics is taken into account. (The energy-momentum tensor of quantum fields diverges near a CTC). I don't think there is a full proof of this sickness, but example by example shows it to hold so far. This lead Hawking to the 'Chronological Protection Conjecture'. Basically nature will always find a way to destroy a time machine. But as I say, this conjecture is not fully proved as far as I know. One would need to understand the full quantum theory of gravity to really address the question of CTC being physical. Link to comment Share on other sites More sharing options...
swansont Posted February 22, 2015 Share Posted February 22, 2015 No, not this thread, it'd be pretty stupid to disprove my theory. The theory of "travelling at c, slows down time, but you wouldn't", is actually not disproven in my opinion. We haven't come to the extent of having superior technology to find that out. We'll leave that theory be for a couple years. So that's not a subset of "travel at any speed and time slows down" which is well-established? 1 Link to comment Share on other sites More sharing options...
Strange Posted February 22, 2015 Share Posted February 22, 2015 This lead Hawking to the 'Chronological Protection Conjecture'. Basically nature will always find a way to destroy a time machine. There were some amusing suggestions that the initial problems with the LHC were because it could act as a time machine and therefore nature would never let it start up. 1 Link to comment Share on other sites More sharing options...
Mr. Astrophysicist Posted February 22, 2015 Author Share Posted February 22, 2015 (edited) So that's not a subset of "travel at any speed and time slows down" which is well-established? No, I'm not saying that. Travelling at any speed slows down time, but travelling extremely quickly or quicker, it slows down time. Well it is all relative. You have not really presented a theory here. In physics a theory is a mathematical model that we can use to model nature. A theory is 'good' if it matches nature well enough for our purposes, or 'bad' if not. So you will need to present some mathematical details on travelling at the speed of light (relative to what?) and how this effects the measurement of proper time. Well, it is not just an issue to technology. The theory of special and general relativity tell us that (locally) a massive body cannot travel at a speed equal to or greater than the speed of light as measured by an inertial observer. In short, no-one can measure the speed of a body to be the speed of light. There are some 'get-outs' here. You can use the geometry of space-time to have motions that break the global speed of light, such as using a wormhole or a warp drive. Both of these could be used to create a time machine or a CTC (closed time-like curve) as we rather call them. The problem is that such devices seem to require 'exotic matter' such as matter with negative mass. It may be possible to use quantum effects to generate the necessary negative energy densities. However, so far all known time machines are sick. They suffer from real problems when quantum mechanics is taken into account. (The energy-momentum tensor of quantum fields diverges near a CTC). I don't think there is a full proof of this sickness, but example by example shows it to hold so far. This lead Hawking to the 'Chronological Protection Conjecture'. Basically nature will always find a way to destroy a time machine. But as I say, this conjecture is not fully proved as far as I know. One would need to understand the full quantum theory of gravity to really address the question of CTC being physical. Thank you for the message ajb. I shall try to fully understand quantum theory of gravity to try prove the conjecture. I misunderstood the concept and your message helped a lot. While on this topic, the reason of CPC (Chronological Protection Conjecture), is actually and possibly to protect space and time of universes or this universes from paradoxes, right? Or that's just my opinion. Edited February 22, 2015 by Mr. Astrophysicist Link to comment Share on other sites More sharing options...
ajb Posted February 22, 2015 Share Posted February 22, 2015 (edited) I shall try to fully understand quantum theory of gravity to try prove the conjecture. I don't think you understand the magnitude of this task. Anyway, the conjecture is formulated in the context of semi-classical gravity, that is the quantum theory of fields on a curved background. It is a very specialist topic that is very technical, given what you have said already I would not expect you to really understand this very soon. Just be aware that adding quantum theory to the fields on space-time seems to destroy time machines, but this is not a full general theory. We don't have a proper full theory of quantum gravity to test these ideas past semi-classical gravity. People try to argue that they expect some results to hold true in the full theory, but without a full theory we cannot really say. I misunderstood the concept and your message helped a lot. While on this topic, the reason of CPC (Chronological Protection Conjecture), is actually and possibly to protect space and time of universes or this universes from paradoxes, right? Or that's just my opinion. It would ban time travel and so any related paradoxes. Edit: Minor typo Edited February 23, 2015 by ajb 1 Link to comment Share on other sites More sharing options...
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