# Physics question

Jaxon Myers

is forward time travel possible?

Sebastian Rivera

yes
backwards isn't

Jeremiah Wilson

yes, we are doing it right now

Ayden Bennett

depends
Mexicans can only go back

Jordan Lee

is backwards time travel impossible because i could create paradoxes or are there other reasons?

Nicholas Hernandez

it's impossible because it would require negative energy or negative mass.

such things, to our current level of knowledge are not possible

Alexander Peterson

so we already know what would be required?

Sebastian Gray

it's impossible because there's no way to do it.
Forward is achieved by theoretically speeding objects up as close to the speed of light as you can. Or something like that- whatever it was I read five years ago or something.

"In 2017 researchers at Washington State University demonstrated negative effective mass experimentally by cooling Rubidium atoms with lasers"
Jewpedia article

if im traveling at the speed of light and hold a mirror in front of me, do i see my reflection?

Jacob Jenkins

Forward is achieved by theoretically speeding objects up as close to the speed of light as you can.
does that mean, that light does travel through time?

Dylan Foster

if im traveling at the speed of light and hold a mirror in front of me, do i see my reflection?
i also want to know that

Brody Ortiz

It's a logical conclusion of our current understanding of how time - space works.

The way how it works is effect of mass and energy existing as they are. If there were negative mass and or negative energy time would have to accelerate backwards.

This is of course very hypothetical because we do not know if in such a scenario, those rules would still apply.

Just like when you look at quantum level events most of known physics stops making sense.

"In 2017 researchers at Washington State University demonstrated negative effective mass experimentally by cooling Rubidium atoms with lasers"

Just skimmed about it, dont have time now to read more, but ti looks like they made atoms act like they had negative mass with lasors and not have de facto negative mass

Yes you would, this is the bacist of revised theory of relativity. Light for you still travels at C, relative to you, because it bounces from your face. But for someone watching from the side, both you and the mirror would be invisible.

On the other hand you cannot achieve C because for that would would need infinite energy. It's simply impossible for a object with mass

Are you all really interested or is this trolling?
This is middle school physics stuff. Fun, but still very basic

Jayden Sanders

It's all relative, thus the theory of relativity. Basically if you travel at the speed of light, you don't really feel any different or age any differently. However to an observer watching you travel at the speed of light, they would watch you go so fast an disappear and continue to age and move through time normally. so what happens is when you hit the speed of light, you are experiencing time on something near to 7 years for every 1 minute or something similar. To people that are not moving at the speed of light, they just experience time as 1 minute per every minute.

Easton Cruz

Are you all really interested
i'm really interested. i was an idiot in middle school. thanks!

John Fisher

Well that'd be the logical conclusion, but it's not quite like that. Again, I skimmed this many years ago in some physics textbook or on the internet, I can't even remember. This is just me postulating an educated guess.
Light is a wavelength, not a particle, so it doesn't behave like say an apple would if you sped it up to that speed. "Travel forwards through time" is also pretty glorified for what you'd actually achieve with your light-speed apple. The time difference isn't vast, it's not years and years like in films, but probably rather in the margin of several minutes faster in time. However, the closer that you got to the speed of light, the more exponentially faster in time your particle would go.

This would have to do with bending of space-time (like star-trek warp drives), which is also theoretically possible but not proven yet.
Imagine that you have a sponge, and a particle travels through the sponge at a fixed rate. If you compress that sponge, the particle, though it's going the same speed as it was before, will get to the other side of the sponge much faster.

Nolan Miller

Light is a wavelength, not a particle, so it doesn't behave like say an apple would if you sped it up to that speed

Pretty much this.
"for light" it does not travel through time, because it's masless.
It's a wavelengths with energy through, so for us it creates a golden standard for time which is C

So for us, time is basically just expression of length the light travels, and it's 299792458 meters for second.

So if you could stop time, just theoretically, to absolute standstill you would create a world of absolute darkness because without time there is no light.

Carson King

and we are still at the point where we think that we can't go any faster that light?

Levi Martinez

thaN light?

Joseph Baker

ok so it works like in the picture above. so say you have a timer right and there are two ways of looking at it. one facing the timer while it is not moving and one from the side while the timer is moving

the timer works by bouncing a laser beam, light, between two mirrors and for every two bounces you get a beep or a ding or something. this beep is basically an interval.

this is why you could, travel through time by going incredible fast, time basially begins to slow down compared to your velocity through space time as you approach the speed of light.
when looking at the timer while it is not moving, the light only has to travel up and down in order to complete an interval. this is the top half of the picture.

But say you're looking at the timer from the side while its moving. the light , to your field of view, looks like it has to travel a much longer distance, the bottom of the picture. typically we would assume that the light just speeds up to travel the longer distance between the two mirrors. however, this is not the case, because light can only travel at one speed. the speed of light. so as it turns out, a timer standing still and a timer moving actually do not produce the same interval because the timer moving actually takes longer to complete one beep.

Christian Howard

who is we?

Juan Rivera

you and I

Jace Brooks

not traight up

to accelerate any mass to C you would need infinte energy. on the other hand, object with any mass if were somehow travelling at C would collapse at itself because it would have infinite mass

You can circumvent it through via time space manipulation.

You travel with 1/2C which still required impossible amounts of energy but is not impossible de facto. Then you compress time space in front of you and strech it behind you. So for you you travel with 1/2C, but for an observer you travel at effective FTL, no laws broken.

Other way would be to create wormholes, which is the idea of straching and compressing time space put to incredible level

Daniel Scott

do i get this right, that the more a car (with lights on) accelerates the light particles in front of the car have to slow down?

Gabriel Sanchez

you can't accelerate to speed of light but you can go faster if you know the tricks
speaking from experience

Thomas Wood

You travel with 1/2C which still required impossible amounts of energy but is not impossible de facto. Then you compress time space in front of you and strech it behind you. So for you you travel with 1/2C, but for an observer you travel at effective FTL, no laws broken.
aka warp drive?

Josiah Nelson

more like the car is moving faster and faster until is is so fast that it is going at the same speed of the lights it has, but yeah that is kinda the general principle.

Robert Walker

The concept of time is merely marked change in the physical. This change is non-reversible, especially at the universe-scale.
What you are asking is essentially "is change possible"? And the answer is an obvious yes.

Julian Stewart

aka warp drive?
yup

Gavin Jenkins

if its only change in the physical why does change go faster the faster i travel?

Robert White

the universe is expanding. time is a measure of that expansion and the speed of light is relative to the increase in volume of the universe. today's mile is yesterday's furlong and the speed of light increases over time for an objective observer.
the world is obvously flat, /pol/ always right and Trump is the emperor divine.
prove me retarded

Connor Smith

the universe is expanding. time is a measure of that expansion and the speed of light is relative to the increase in volume of the universe. today's mile is yesterday's furlong and the speed of light increases over time for an objective observer.
do we really increase in size? or was that shitposting?

Xavier Rivera

Yes, but not as much as you do. Fatass.

Wyatt Brooks

speed of light is constant dumbass

universe is expanding everywhere
new space is created between atoms
[universe]
[ u n i v e r s e ]
[ u n i v e r s e ]
distant parts of universe are already "moving" away faster than light

Kayden Edwards

Not only did you steal this question from Einstein, You neglected to listen to his answer. 2/10. would not engage intellectual discussion with you.

Mason Gutierrez

Sleeping makes time go faster and your body doesn't age as fast while sleeping
biology > physics