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Anonymous Fri 26 Feb 10:14:22 2021 No.12758027 View Reply Original Report

Quoted By: >>12758044 >>12758067 >>12758112 >>12758211 >>12759073 >>12759982

Brainlet here so please be patient with me and excuse my retardation.

I understand one requires more energy/force the faster you go, and as you approach the speed of light you will reach near infinite mass thus require near infinite power to accelerate.

But this just doesn't make sense. Let's say you accelerate to 10% of the speed of light, turn off the engines, then turn them back on. Wouldn't this effectively have you start as if you were stationary? How is momentum anything but a matter of perspective for it has no memory?
What is acting on particles in order for them to gain mass?

Anonymous

Anonymous Fri 26 Feb 2021 10:19:54 No.12758036 Report

Quoted By: >>12758040

You didn’t research this for more than 5 seconds

Anonymous

Anonymous Fri 26 Feb 2021 10:21:50 No.12758040 Report

Quoted By:

>>12758036
Mate, I'm retarded. I didn't research it at all because I understand jack shit.

Anonymous

Anonymous Fri 26 Feb 2021 10:23:45 No.12758043 Report

Quoted By: >>12758086

>What is acting on particles in order for them to gain mass?
The Higgs field.
>Let's say you accelerate to 10% of the speed of light, turn off the engines, then turn them back on. Wouldn't this effectively have you start as if you were stationary?
No and I don't know how to elaborate because I'm not sure how you came to that conclusion

Anonymous

Anonymous Fri 26 Feb 2021 10:24:48 No.12758044 Report

Quoted By:

>>12758027
https://www.youtube.com/watch?v=gSKzgpt4HBU

Anonymous

Anonymous Fri 26 Feb 2021 10:37:33 No.12758067 Report

Quoted By: >>12758071 >>12758106

>>12758027
Throw a ball. When it leaves your hand it is no longer being accelerated. But it still maintains momentum until it is acted on by a force. The same applies in space, except friction and gravity are nonfactor, so you lose no momentum from stopping the engine and you maintain velocity.

Anonymous

Anonymous Fri 26 Feb 2021 10:39:01 No.12758071 Report

Quoted By: >>12758075 >>12758076 >>12758103

>>12758067
That's my question, why would it require more energy to accelerate more at that point?

Anonymous

Anonymous Fri 26 Feb 2021 10:40:31 No.12758075 Report

Quoted By: >>12758092

>>12758071
Yes, the amount of force required to accelerate doubles with your weight to speed ratio.

Anonymous

Anonymous Fri 26 Feb 2021 10:40:55 No.12758076 Report

Quoted By: >>12758092

>>12758071
because it takes energy to accelerate further

Anonymous

Anonymous Fri 26 Feb 2021 10:43:42 No.12758086 Report

Quoted By: >>12758091 >>12758102

>>12758043
Another brainlet here: what is disturbing me is that it is not possible to actually be stationary as, for example, the milky way is rotating, so how do we know how far we are from moving at the speed of light?

Anonymous

Anonymous Fri 26 Feb 2021 10:44:56 No.12758091 Report

Quoted By: >>12758117

>>12758086
Relative measurements based on how long it takes for the light to reach us. We're moving somewhere in the 100s of thousands of miles per second range.

Anonymous

Anonymous Fri 26 Feb 2021 10:44:56 No.12758092 Report

Quoted By: >>12758462

>>12758075
>>12758076
I can understand it requiring more energy if it's a continuous acceleration, but I don't understand why it would be applicable to something just floating in space.

Is speed directly tied to mass and whatever mass is gained remains even when the acceleration stops?

I'm struggling to wrap my tiny brain around it. Say everything else in the universe disappears but the object accelerating intermittently. How can it even be known it is moving, and what difference does having the engines on have anyway?

Anonymous

Anonymous Fri 26 Feb 2021 10:47:28 No.12758102 Report

Quoted By: >>12758174

>>12758086
Everything is moving at the speed of light in it's own frame. It's time that changes.
https://www.youtube.com/watch?v=UKxQTvqcpSg&t=

Anonymous

Anonymous Fri 26 Feb 2021 10:47:32 No.12758103 Report

Quoted By: >>12758160

>>12758071
From yourown frame of reference you don't, time dilation etc. only exist to justify the difference between what you see and what the outside sees. Relativity is always discussed between two (ideally inertial) frame of references, because there is no "absolute" speed or favored pov.

Anonymous

Anonymous Fri 26 Feb 2021 10:48:00 No.12758106 Report

Quoted By: >>12758119

>>12758067
>throw a ball then throw it again
This doesn't answer my question. Whatever energy is required to throw it originally can be applied again in addition to the momentum it carries from the original throw. You might need an impossibly large number of throws each time to gain any real speed, but why does it become more difficult to throw?

Anonymous

Anonymous Fri 26 Feb 2021 10:48:43 No.12758112 Report

Quoted By:

>>12758027
>Let's say you accelerate to 10% of the speed of light, turn off the engines, then turn them back on
this is how rocket staging works, but the key metric is that you burn until you run out of gas, throw a new, smaller rocket out of the window, and then burn that guy until he's out of gas too

Anonymous

Anonymous Fri 26 Feb 2021 10:50:10 No.12758117 Report

Quoted By:

>>12758091
Does that mean that if the spacecraft in OP post goes in the wrong direction, it will actually decelerate?

Anonymous

Anonymous Fri 26 Feb 2021 10:50:11 No.12758119 Report

Quoted By: >>12758123

>>12758106
Because to throw it again you need to first achieve the same speed as the ball

Anonymous

Anonymous Fri 26 Feb 2021 10:51:21 No.12758123 Report

Quoted By: >>12758126 >>12758134

>>12758119
Yes, but just swap the thrower in the analogy to the engines on a spacecraft. Thus, the thrower is already at the speed of the ball.

Anonymous

Anonymous Fri 26 Feb 2021 10:52:15 No.12758126 Report

Quoted By:

>>12758123
no, the thrower in that case is throwing balls in order to accelerate himself, and he only has so many balls

Anonymous

Anonymous Fri 26 Feb 2021 10:53:48 No.12758134 Report

Quoted By: >>12758147

>>12758123
Ergo, the engines have to produce enough thrust to match the speed already achieved by the ball.

Anonymous

Anonymous Fri 26 Feb 2021 10:57:37 No.12758147 Report

Quoted By: >>12758160

>>12758134
But isn't speed relative is my point.
Let's say you had an absurdly segmented object in space, and at each stage of decoupling the same acceleration is applied, would it not accelerate despite the acceleration rate remaining the same?
Why does it matter how fast it's going when it's already in space being affected by almost nothing.

Anonymous

Anonymous Fri 26 Feb 2021 11:00:17 No.12758160 Report

Quoted By:

>>12758147
>>12758103

Anonymous

Anonymous Fri 26 Feb 2021 11:05:38 No.12758174 Report

Quoted By: >>12758185

>>12758102
Why not the opposite? Time is constant but it is the speed of light that changes?

Anonymous

Anonymous Fri 26 Feb 2021 11:09:50 No.12758185 Report

Quoted By:

>>12758174
It's not up for debate, people literally observed light having a constant speed and needed to craft theories accordingly.

Anonymous

Anonymous Fri 26 Feb 2021 11:22:26 No.12758211 Report

Quoted By: >>12758462

>>12758027
This is actually a better question than most realise. If you really consider space and time separate, which all physicists did before 1905 and most physicists did until a few decades ago, you'll find that there is no way to make Galilean relativity compatible with Newtonian mechanics in which particles move through only space, and not time. Einstein himself didn't come to think of space and time as one unified entity, but it was Hermann Minkowski who came up with the 4D concept of spacetime. In this new 4D spacetime, each particle has a four velocity which is essentially the "time" derivative in each of 4 axes.

For particles having mass, and at rest w.r.t observer, the particle has 0 spatial velocity and `c` as velocity in the time axis. That's just convention. Once you start accepting this framework of working with velocities, you'll see that the 4 components form a 4D sphere in which the radius is always `c`. You can have any combination of these four components, as long as they add up to `c`. For light, all 3 spatial components add up to `c` and the time velocity is 0, in other words, clocks are frozen for light speed particles. For massive particles, depending on the frame of reference, it can have multiple components in all 4 dimensions, but in the time dimension it can never have a 0 component. Which means that matter always stays "matter", no matter how slow its clock ticks. Another way to understand this is that matter IS a clock. There is no distinction between a clock and matter, the frequency at which matter vibrates could be considered as a clock. Merely accelerating this piece of material to near light speeds won't affect the clock like behaviour of this material but will make it appear to tick slower.

Anonymous

Anonymous Fri 26 Feb 2021 13:02:02 No.12758462 Report

Quoted By:

>>12758211
can you explain that to me like i'm retarded?

also what about this >>12758092

Anonymous

Anonymous Fri 26 Feb 2021 16:40:39 No.12759073 Report

Quoted By: >>12759317 >>12759923

>>12758027
>Let's say you accelerate to 10% of the speed of light, turn off the engines, then turn them back on.
>Wouldn't this effectively have you start as if you were stationary?
Yes.
If you try to add another 10% from your new reference frame it will take the same amount of energy.
The discrepancy comes from the fact that the second 10% will not appear to be an additional 10% from an observer at the starting point of your journey.
This observer would agree that your initial 10% is in fact 10%. The second 10% would appear to be less than 10% so they would say your final velocity is less than 20%.

Anonymous

Anonymous Fri 26 Feb 2021 17:37:01 No.12759317 Report

Quoted By:

>>12759073
Why?

Anonymous

Anonymous Fri 26 Feb 2021 20:15:43 No.12759923 Report

Quoted By:

>>12759073
Who cares about reference frames other than your own? My velocity is 20% of c and I don't ask anyone else for their opinion.

Anonymous

Anonymous Fri 26 Feb 2021 20:37:08 No.12759982 Report

Quoted By: >>12759989

>>12758027
The important thing to note isn't that it requires more energy for you, it requires more energy to the outside observer. Increasing your speed relative to yourself will always require the same amount of fuel, it's just everything around you will not follow that linear scale thanks to time dilation.

Anonymous

Anonymous Fri 26 Feb 2021 20:39:53 No.12759989 Report

Quoted By: >>12759993

>>12759982
So then why is it impossible to reach the speed of light?

Anonymous

Anonymous Fri 26 Feb 2021 20:41:42 No.12759993 Report

Quoted By:

>>12759989
Because movement only exists relative to another object. When you move, you are moving relative to another object, and that value does not scale linearly.

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