beansbaxter
Needs a life
Posts: 5911
|
posted May 24, 2005 10:56 PM
Physics Part 10 - Why can't matter reach the speed of light?
I know you all need another physics dose these days...so here we go:
Just wondering, if something was in a vacuum, why couldn't it accelerate forever until it reached the speed of light? What forces would counter the acceleration?
   
|
Otis
Needs a job
Captain Kickstand
Posts: 3028
|
posted May 25, 2005 03:27 AM
The faster you go, the heavier you get.
|
billbisby
Novice Class
Posts: 96
|
posted May 25, 2005 03:59 AM
Just because!
|
ozzy
Needs a job
need guberment cheese
Posts: 3172
|
posted May 25, 2005 04:09 AM
There will still be matter in a vacuum that will cause drag
|
Otis
Needs a job
Captain Kickstand
Posts: 3028
|
posted May 25, 2005 07:29 AM
You'd better be protected too, cause without some heavy duty shielding of some sort, you'd be toast.
|
frEEk
Administrator
ummm... yeah
Posts: 9660
|
posted May 25, 2005 10:24 AM
in a true theoretical vacuum there would be no matter to cause drag and nothing requiring protection. of course this is just a theoretical that cannot exist in reality (can it?).
i don't think u could ever reach the speed of light because that would require an infinite amount of energy thanks to the increasing mass that Otis mentioned. however, you could get infinitesimally close to the speed of light and would continue to get closer the more energy u put into accelerating. of course this is basically all guesses as i have little education in this area.
|
deathpulse
Pro
Posts: 1688
|
posted May 25, 2005 03:34 PM
Well, interesting things happen as an object is accellerated toward the speed of light in a vacuum. It is kind of true that the faster you go the "heavier" you get. - but more specifically, the faster you go, the more mass you displace. This causes interesting things to happen with gravity and of course with the energy required to move to a higher velocity. In addition to the increased energy requirements, time is also affected (due to gravity) and as you get very close to the speed of light, time actually slows down relative to a slower movign observer. Essentially, time will appear to stand still if you get close enough to 186,282 mps in a vacuum. A similar quirk is thought to happen in close proximity to the event horizon on a black hole - but that is for another day's theoritical physics lesson  .
|
lizard
Pro
Modulator
Posts: 1483
|
posted May 25, 2005 04:32 PM
What does Vince have to say about this?
|
zx12adam
Member
Posts: 878
|
posted May 25, 2005 05:54 PM
As EVERYone knows if you recalibrate the flux capcitor to .405dbc's and compensate for the diode to the power of ten(10) with the actuator increased essentially to approximately 186,282mps you could microwave a bowl of chili...
... I stayed at a Holiday Inn last night.
The problem with talking about something I know nothing about is I never know when I'm done.
____________
CBR1000RR
Best Literbike: Performance Bikes, Superbike, BIKE, MCN, Road Racing World, and Motorcycle USA
|
deathpulse
Pro
Posts: 1688
|
posted May 25, 2005 06:27 PM
Well - keep in mind this is all theory - if you can come up with something that is plausable and has a general basis in math... then it can be the latest and greatest viewpoint .
|
redelk
Moderator
Please... speak to the hand.
Posts: 3212
|
posted May 25, 2005 06:39 PM
Why can't matter reach the speed of light?
Probably due to a crappy map in their Power Commander.
____________
There are only three sports: bullfighting, motor racing, and mountaineering; all the rest are merely games.
-Ernest Hemingway
|
eastbaydave
Needs a job
Posts: 2245
|
posted May 26, 2005 05:26 AM
I felt like the Saturn V on the launchpad after last nights dinner....:P
____________
Enjoy the ride!
02' ZRX1200
00' ZX12R sold
|
Bagster
Zone Head
Posts: 630
|
posted May 31, 2005 04:53 AM
 Edited By: Bagster on 31 May 2005 05:59
How about solar winds?
Wouldn't they affect or counter-affect acceleration?
Scientists planned on using them to head out into space, how far would they be useful away from the sun?
If they are useful heading away from our sun for a long distance, wouldn't that mean that every star in front of the ship would be sending solar wind back at the ship (in varying degrees of intensity ) causing resistance.
If you are not using solar sails of course the resistance would be much less, but how much would it be?
What about other forces we don't really know much about yet, such as dark matter and its affect?
The engine to power something to the speed of light would have to have particles coming out the tailpipe greater than the speed of light to overcome any kind of "drag" created by any of the above.sources, including space dust which would be quite substantial at near light speeds
Since we don't know of any particles that are faster than light to power this ship, it would need a "perfect" environment to reach that speed, and we all know that nothing is perfect.
:-)
|
Otis
Needs a job
Captain Kickstand
Posts: 3028
|
posted May 31, 2005 06:51 AM
Bagster, your tailpipe thoughts are not valid. There is no way in hell we'll ever get even close to .10c with a reaction drive. Also, solar winds outside our heliosphere are irrelevent. We could harness the power of our solar winds inside our system but once your out of that, it too becomes irrelevent.
|
zx11_12
Expert Class
Posts: 207
|
posted May 31, 2005 10:43 AM
Edited By: zx11_12 on 31 May 2005 11:46
Actually, tachyons are theoretical particles that travel faster than light, but they have no mass, so they are uselss for acceleration. Well, thier mass is a square root of a negative number, which is an imaginary number....still useless for accelleration even if we could harness them.
And Einstein never said it was impossible to go faster than light, he said is was impossible to go the speed of light. If we could somehow skip past the speed ofl ight without ever actually touching it, we could go faster than light. On the other side of the speed of light, it actually takes energy to slow down.
____________
"There is only one basic human right, the right to do as you damn well please. And with it comes the only basic human duty, the duty to take the consequences."
PJ O'Rourke
|
Bagster
Zone Head
Posts: 630
|
posted June 01, 2005 04:38 AM
I agree Otis, I wasn't trying to validate light speed travel.
I don't think you understood what I was saying.
I wasn't trying to use solar winds as a method to reach light speed, only as an example why we can't reach light speed due to their existance.
What kind of drive are we going to use then Otis?
OK, hows this one.
You have an engine that is tossing particles out the tailpipe at light speed and producing thrust effectively.
Lets say you actually reach light speed with this setup.
Wouldn't that mean that the particles that leave the engine are just being laid out in a line through space with no rearward motion? ( not that this can actually happen)
This brings me to the conclusion that as you come closer to light speed you get less and less thrust out of your "reaction drive".
What shall we do?
|
frEEk
Administrator
ummm... yeah
Posts: 9660
|
posted June 01, 2005 04:27 PM
bagster, 2 small points:
beans' question stated that being in a vacuum was a condition of the hypothetical. assuming standard physics assumptions, that would be assumed to be a theoretically perfect vacuum, not the real world next best thing, which is open space as u are refering to.
as to a thrust engine no longer working as u get faster, that is false. it is all about impulse, so absolute speed does not matter. i _think_ you are correct about the possibility of the situation where the ejected particles stand dead still in space, but think about playing pool, where u hit one ball with another, the first ball stops moving entirely while the second ball takes off at the same speed the first was moving pre-impact.
|
vozizm
Needs a job
Got Nothing Witty To Say
Posts: 4417
|
posted June 03, 2005 07:57 AM
you guys give me a headache!
____________
VOZ
|
Otis
Needs a job
Captain Kickstand
Posts: 3028
|
posted June 03, 2005 09:57 AM
Edited By: Otis on 3 Jun 2005 10:58
Not trying to slam your thoughts at all bagster. If fact your question about thrust paticals, once theoretically reaching the speed of light, has my mind in a twist. Very interesting, I've never thought of that before because I'm pretty sure it would be impossible to reach those speeds with a reaction drive. In my humble opinion, the only way we will be able to reach even close to the speed of light would be with some sort of wedge drive. A drive capable of distorting gravity. For example, if we were able to design some sort of, and I'll use the term loosly here to help get my theory across, "magnet" to project a gravity well in front of a ship to, in effect PULL, not push a ship to speed. Think of it as being able to project a black hole in front of your ship at a static distance from the ship. Another possibily is if we would be able to find gravity threads and chart them, tehn if we could create some sort of energy sail, say hundreds of miles across on either side of the ship to "catch" the threads and ride them.
Anyway, I'll be long dead when this kind cool stuff happens. Great discussion fellas.
|
frEEk
Administrator
ummm... yeah
Posts: 9660
|
posted June 03, 2005 11:24 AM
i remember lazer sails being discussed as a possibility for a quick trip to the outer parts of the solar system not that long ago. however i suspect even those would be less effective as speed increased. this also brings up the very important distinction between approaching light speed (even if the difference is infinitesimally small) and actually hitting high speed. with the lazer sails for example, you could theoretically approach light speed given infitite time and space, but never quite reach it cause u would be outrunning the lazer once you reached it. i still think actualyl hitting exact light speed is impossible even under theoretically perfect conditions and given a method of drive that would work up to light speed, due to the issue of increased mass.
|
Otis
Needs a job
Captain Kickstand
Posts: 3028
|
posted June 03, 2005 11:40 AM
Edited By: Otis on 3 Jun 2005 12:45
I totally agree Freek. You may be able to get close, but you won't hit it. Best case and most probable is we'll find and master wormholes before we're ever able to hit close to light speed. Realistically, if we are ever to become star travelers, the speed we can move in real space will be token and just for menuevering "in-system". To travel FROM system to system, there will have to be junctions. I mean even if we hit light speed we're still 4.5 years travel time in real space from Centauri, the closest system.
|
Bagster
Zone Head
Posts: 630
|
posted June 04, 2005 04:32 AM
The black hole projector engine is a good idea but would be very difficult to make.
You would need some kind of "tractor beam" (for lack of a better term) that is stronger than the black hole itself, to keep the ship from being sucked into its own black hole?
(Talk about a bad day!)
I'm thinking we will probably just scam the technology off some unfortunate space travellers.
They're on the way right now. :-D
|
|
|
HOME
NEW TOPIC