## Relativity?

How does science work? And what's all this about quantum mechanics?

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ken
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### Re: Relativity?

davidm wrote: Sun Oct 15, 2017 1:55 am
ken wrote: Sun Oct 15, 2017 12:08 am
Are you unable to answer the question, or do you just prefer not to answer because of the following clarifying questions that I will then ask?
I HAVE answered these questions, dumb fuck. So has uwot.

Are you absolutely sure?

Could have you missed some thing, or, is it always Me who is missing some thing?
ken
Posts: 2075
Joined: Mon May 09, 2016 4:14 am

### Re: Relativity?

davidm wrote: Sun Oct 15, 2017 2:28 am
ken wrote: Sat Oct 14, 2017 11:50 pm Now, WHY would it take the human being in the ufo supposedly FAR less "time" than say light would take to travel the exact same distance, especially when light is travelling faster?
Read this: Ten Minutes to Alpha Cenatauri? (You won’t read it, of course.)
Is that an assumption or a known fact?
davidm wrote: Sun Oct 15, 2017 2:28 amHint: Length contraction. (Which I discussed, albeit briefly, upthread. Did you gloss over that too in your frantic impatience to be the internet rando who overturns standard science?)
There is no thing to overturn. There are, however, things that can and need to be put into their true relative perspective, that is if you want to see the real and true picture of things.
davidm wrote: Sun Oct 15, 2017 2:28 amFrom the above link:
To see how this works, let us suppose our spaceship heads to Alpha Centauri at 90% of the speed of light.  According to the Earth-bound observer, the trip should take 4.86 years.  According to the person on the spaceship, however, the trip takes only 2.12 years!
But does the actual trip take 2.12 years, or is that only what the person the spaceship observes?

Can observations be wrong?

What year does the person from the spaceship observe when they land on alpha centauri and look back at earth?

Does this observation fit in with their previous traveling observation?
davidm wrote: Sun Oct 15, 2017 2:28 amThis is quite surprising — according to our argument, it seems that the spaceship pilot can reach Alpha Centauri in less time than it would take light.  At first glance, it would seem our spaceship is traveling faster than light, since it travels 4.37 light-years in 2.12 years.  However, what in fact happens is that the distance to Alpha Centauri becomes shorter for the person in the spacecraft.

Italicized by the author, not me.
Does the distance to alpha centauri, in fact, actually become shorter, or just appears to become shorter for the person in the spacecraft?

Traveling at the speed of light it would obviously appear as though distances become shorter because it obviously appears as though you are going to get there instantly, and in a sense it really feels like this. However, how can a person on a spacecraft traveling less than the speed of light arrive somewhere else quicker than light can?

What appears to happen does not always, in fact, happen.

Obviously things would NOT contract just because one is traveling at a faster speed, but also just as obvious is to WHY it appears that things contract. What appeared to be the case would be proven right or wrong when they arrived on alpha centauri and looked back at earth. Then things would be brought back into their true perspective.

Think about what is seen when looking back at earth when arriving at alpha centauri after traveling at the speed of light.

Also, as proposed in that link traveling to alpha centauri in 10 minutes or less is very close to how long light takes to get just from the sun to the earth. It is quite often said that human beings can not travel at the speed of light but now it is being proposed that human beings could, somehow, travel much faster than the speed of light.

The actual truth is sometimes quite more suprising than the perceived truth.
ken
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### Re: Relativity?

davidm wrote: Sun Oct 15, 2017 2:51 am
ken wrote: Sat Oct 14, 2017 11:50 pm Also, does any one have an answer as to why you, human beings, can do a thought experiment when discussing traveling anywhere between zero and just short of the speed of light, but it seems near impossible to get you human beings to do a thought experiment in regards to traveling at the speed of light? It is like their brains just completely block them from even being able to fathom the idea, let alone being able to see and discuss it?
Actually, in this very thread, people HAVE imagined humans traveling at the speed of light! I ask again, Can you not properly read?
Have they, if so, then how long does it take a human being to travel 4 light years traveling at the speed of light?
davidm wrote: Sun Oct 15, 2017 2:51 amHowever, such speculations are otiose, because humans CANNOT travel at the speed of light.
Who cares? It is just a thought experiment.
davidm wrote: Sun Oct 15, 2017 2:51 amBut if (for example) atoms could, as uwot has postulated for the hell of it, and if you understood the principle of the light clock, you would understand his point that there could be no photon exchanges between atoms moving at c. Of course you don't understand. As Trump would say, Sad!
Once again, another one who will NOT look at a thought experiment in relation to a human being traveling at the speed of light and will instead look from the brain only and reply from what information has been fed into it. The same one will although look into what it would take to build an, at the moment, impossible light clock, but will still shy away from looking at what it would take to travel at the speed of light.
ken
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### Re: Relativity?

davidm wrote: Sun Oct 15, 2017 3:43 am For a spaceship traveling at 90 percent the speed of light toward Alpha Cetauri:

Earth observer: Alpha Centauri is 4.37 light years away.

Spaceship observer: Alpha Centauri is 1.90 light years away!

Who’s right?

They’re both right!
They are both just observations, from two different people who naturally have different views from which they are looking from at the start, let alone the actual fact of the vastly different advantage points from which they are now gaining their points of views from. There is one right answer, which can be solved and shown with the right formula. However, people already say they KNOW what the answer is already, and if others do not follow nor accept that, then they must be to stupid to understand.

I have already described and thus shown two different ways, in this thread, about how to obtain the true and right view of this. I have described and shown how to gain the truest and fullest picture in other ways throughout this forum. If they have not been noticed and/or not understood, then that is fine. I am not here in this forum, to be understood, only to learn more. It, however, other things come to light, then so be it.
uwot
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### Re: Relativity?

ken wrote: Sun Oct 15, 2017 4:42 amIn regards to if a physical body can exist at the speed of light, I KNOW that is it said to be IMPOSSIBLE, and from what you have said here has made Me realize much more about WHY it is said to be IMPOSSIBLE. It was very informative, makes a lot of sense, and very easy to understand, so I thank you a lot for that. BUT I was NOT and NEVER was asking about any thing in relation to a human being being able to travel at the speed of light. What I WAS asking and still am is IF a human being could possibly travel at the speed of light, what then would happen in relation to the time is takes to travel a certain distance?
I think the problem is that many people think that there is some objective time, according to which the question 'How long was there nothing, before the Big Bang happened?' is answerable. Maybe there is, but from a human perspective, every method we have of measuring 'time' is dependent on our counting events that happen to material objects. A year is roughly how long it takes the Earth to orbit the Sun. A month is roughly how long it takes the Moon to orbit the Earth. A day is how long it takes the Earth to spin on it's axis. At that point it all gets arbitrary, because you can divide a day up any old how you like. In the west, we happen to have adopted the model of the ancient Egyptians and Mesopotamians of dividing a day into 24 hours, dividing hours by 60 for minutes, and minutes again by 60, for seconds. For day to day purposes, 'the time' is just a convenient way to describe the position of the Earth, in relation to the Sun and the Moon.
For scientific purposes a second is defined as "as the duration of 9 192 631 770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium 133 atom" ( https://en.wikipedia.org/wiki/Second ) If you read the article, you will see all the stuff that has to be accounted for, including that the clock is at rest, because if it is moving, then the number of transitions will differ for the same fundamental reason that the pulses in Einstein's light clock change.
ken wrote: Sun Oct 15, 2017 4:42 amWhat I was asking was in relation to 'time' IF it WAS possible to travel at a certain speed, namely the speed of light.
The thing is, even if there is some stuff that is 'time', we have no method of measuring it directly; all we can do is count things happening and the frequency of things happening is subject to variations caused by, among other things, the speed at which it is moving.
uwot
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### Re: Relativity?

ken wrote: Sun Oct 15, 2017 4:33 amFurther to this you explained how a LIGHT clock reacts to traveling at speed, relative to a light clock on earth, right? My question here is in regards to a "normal" clock, which has NOT yet been answered nor explained.
Well, it was a few pages back, but yes it has:
uwot wrote: Thu Oct 12, 2017 12:44 pmOK. Assume that the speed of light really is as fast as anything can go. Suppose you have a grandfather clock travelling at c. If, in the simplest example, the pendulum is swinging in the plane of movement, it could swing backwards, but to swing in the direction of motion, it would have to exceed the speed of light; in which case, you have to abandon the premise that c really is the speed limit.
surreptitious57
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### Re: Relativity?

ken wrote:
how long does it take a human being to travel 4 light years travelling at the speed of light
A human being will take no time at all to travel anywhere if travelling at the speed of light

Nothing that travels at the speed of light experiences time. Regardless of the distance it travels. Photons have been observed travelling at the
speed of light all the way back to the Cosmic Microwave Background which occurred just 380 000 years after the Big Bang. But they can travel
from then to now in no time at all which is I3 billion years. They will carry on travelling in vacuum forever. As their lifespan is literally infinite
And they are the only physical entity known to have that capability. But even so they will never actually experience time during their lifespan
Impenitent
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### Re: Relativity?

local time still moves

if one travels for 4 years, then one travels for 4 years - distance doesn't matter

-Imp
surreptitious57
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Joined: Fri Oct 25, 2013 6:09 am

### Re: Relativity?

That depends on frame of reference. Anything travelling at the speed of light will not experience time
while an observer watching it sees it travelling through time. Time is therefore not absolute but varies
depending on speed and frame of reference and therefore does not pass at the same rate for everyone
davidm
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### Re: Relativity?

ken wrote: Sun Oct 15, 2017 5:59 am
Is that an assumption or a known fact?
Known fact.
But does the actual trip take 2.12 years, or is that only what the person the spaceship observes?
It takes 2.12 years in his frame. Actual fact.
Does the distance to alpha centauri, in fact, actually become shorter, or just appears to become shorter for the person in the spacecraft?
It actually is shorter. Really and truly.
What appeared to be the case would be proven right or wrong when they arrived on alpha centauri and looked back at earth. Then things would be brought back into their true perspective.
One hundred percent wrong.

There is no 'true perspective' (technically, no preferred frame). That is the whole point of the theory.

It is obvious by now that you either cannot or will not grasp this. It's exactly like PauloL with evolution.
davidm
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### Re: Relativity?

If Ken really wanted to learn about this, he could read a few books, take a class, or even use Google!

Did it ever occur to Ken that Albert Einstein asked, "what would it be like if a human could travel at the speed of light? What would he experience?" And of course Ken could find the answer to these questions with a little Googling, now couldn't he?

Of course, these gadankens by Einstein eventually showed him that humans cannot travel at light speed.

So today, to ask the question: "What would a human experience if he could travel at the speed of light?" has only the following answer:

If a human could travel at the speed of light, relativity theory would be wrong.

But it's not wrong.

So a human can't travel at light speed.
davidm
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### Re: Relativity?

ken wrote: Sun Oct 15, 2017 6:04 am

Have they, if so, then how long does it take a human being to travel 4 light years traveling at the speed of light?
Just to humor you for a moment, let's say god made an exception for one human being to travel at light speed, while the theory of relativity otherwise completely holds.

The answer would be that from his perpspective in this miracle frame, the human would travel zero distance in zero time. How a human brain would function in zero distance at zero time is beyond me, though. Maybe another miracle from Jesus?
uwot
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### Re: Relativity?

davidm wrote: Sun Oct 15, 2017 5:03 pm
ken wrote: Sun Oct 15, 2017 5:59 amDoes the distance to alpha centauri, in fact, actually become shorter, or just appears to become shorter for the person in the spacecraft?
It actually is shorter. Really and truly.
Wouldn't that demand an absolute measure of space?
thedoc
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### Re: Relativity?

ken wrote: Sun Oct 15, 2017 5:00 am Also, when the human being in the ufo land on the other planet and look back to earth, what would the date be that that human being was seeing on earth, and, what would the actual date be on earth?
If the Humans that have traveled to Alpha Centauri at near light speed could look back and see instantly, they would see the Earth at the current date, otherwise they would see it as it was in the past, based on the length of time it takes the light to get to Alpha Centauri or 4.37 years, and it would take them a bit longer than that to get there, depending on what fraction of the speed of light they were traveling at.
davidm
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### Re: Relativity?

uwot wrote: Sun Oct 15, 2017 6:03 pm
davidm wrote: Sun Oct 15, 2017 5:03 pm
ken wrote: Sun Oct 15, 2017 5:59 amDoes the distance to alpha centauri, in fact, actually become shorter, or just appears to become shorter for the person in the spacecraft?
It actually is shorter. Really and truly.
Wouldn't that demand an absolute measure of space?
It's actually, really true in his frame. In the earth frame, it's not true.