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Message 1899957 - Posted: 9 Nov 2017, 2:37:43 UTC - in response to Message 1899952.  

I would like to revisit this 100 years from now and see how much of this has proven to be utter nonsense.

Bob, LIGO has proven this to be fact, spacetime is real and time dilation is real as demonstrated by GPS among many examples.
I f empirical evidence isn't good enough for you I'm sorry.
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Message 1899959 - Posted: 9 Nov 2017, 2:40:44 UTC - in response to Message 1899952.  
Last modified: 9 Nov 2017, 2:50:37 UTC

Really it should not be too difficult here, meant for both of you.

I think that we sometimes could be left thinking about the tools which could be used for that of a subject, including possible thinking,
which could mean possible Philosophy.

Einstein, like a couple of others, could perhaps think that everything is "Relative" and next both to that of subject, as well as thought.

If we make it "The Day After" for that of a movie for such an event, we are not supposed to be speaking of yesterday, but rather the day for today, literally.

A Chamaleon is perhaps not supposed to alter its shape, but rather its possible appearance, including that of coloring, but the four phases of the Moon could also be telling
about the way it is supposed to orbit the Earth.

Space is supposed to be explained by the Force of gravity and next that the notion of time could mean possible change.

Therefore ending lost in both space and also time could be a good explanation here.

We are always supposed to predict events in the future on the basis of that of time itself, so again time could be a constant, but perhaps next not so.

"Where are we coming and where are we going" are common questions which could be around, except for such a thing as time travel, or any Philosophical questions
which might be asked.

"Lack of an absolute reference frame" and except for perhaps not only on my mind, it also is stated in the article about Special Theory as well, a little down the page,
above that for Lorentz transformation, or rather "Reference frames, coordinates, and the Lorentz transformation".

To me this appears almost like Logic for that of a given thinking, except for perhaps any Logic itself when it comes to a subject.

An "Instantiation" could perhaps be an expression for that of a moment of time, if not perhaps an event itself.

If one given thing could perhaps be explained with something else, making it what it is not supposed to be, we always could be having both different explanations,
as well as Laws and Equations for a subject.

If a Prophet could perhaps be telling about a given future, it perhaps is not any speculation either, but rather that of a given knowledge based on thought.

Our ways of proving a couple of things could be quite different than making any guesses about a possible future, except for making it such a thing as Religion and Faith.

Is that of inflation, or the "Inflationary Universe" such a thing which could be explained by means of the Laws of Physics, or perhaps that of gravity?

There should always be a difference between an assumption and the fact that at least we could know about the Universe as it is today and also was in the past.

Make it that of an Prediction and you also could be having an idea, except for any time travel itself, which also could be possible.

If Einstein could be able to come up with such a Frame of Reference, also we should be guessing the possible consequences as well, if not making it an estimate for such.
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Message 1899962 - Posted: 9 Nov 2017, 3:20:23 UTC - in response to Message 1899957.  

I would like to revisit this 100 years from now and see how much of this has proven to be utter nonsense.

Bob, LIGO has proven this to be fact, spacetime is real and time dilation is real as demonstrated by GPS among many examples.
I f empirical evidence isn't good enough for you I'm sorry.

You aren't the only one posting a hypothesis here and I wasn't specifically referring to your pet theory. But I am also not sure that LIGO has provided an infallible proof.
Bob DeWoody

My motto: Never do today what you can put off until tomorrow as it may not be required. This no longer applies in light of current events.
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Message 1899965 - Posted: 9 Nov 2017, 3:38:20 UTC - in response to Message 1899955.  

The thing most don't get is why time seems faster as you are heading to something. That is because you are overtaking the past. At your place you can only know about something after a photon takes a trip from the place it happened to you. So as you close the distance towards the source you run into the photons sooner than if you stayed put. This usually is thought of as the pitch of a train whistle or the Doppler effect. So red light is now blue. But red is the frequency or how many ticks of the light clock, blue is more ticks of the clock (as timed by your clock)

The Doppler effect makes sense to me because I've experienced it, but turning that into an understanding of why a speed of light Alpha Centauri trip would look longer to those on earth than me is still out of my grasp.


Sitting still you see the photon has a distance between the mirrors to go. As the you and the clock move faster the photon has to travel the distance between the mirrors and the distance forward you have gone. So the ticks are now farther apart. Most people understand that.

That sort of makes sense - That the photon of light has to travel further to get back to point A because you're still in motion, but the clock at point A is ticking the same way as the clock at point B(me), isn't it? What I mean is, if I looked at the clock in my super fast traveling spaceship, the second hand would still be moving at the same pace as the second hand of a clock on earth, right? If not, that is where my misunderstanding takes place.
The mind is a weird and mysterious place
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Message 1899969 - Posted: 9 Nov 2017, 4:13:23 UTC - in response to Message 1899963.  

Fully agree with you because again slapping my fingers here and it could also happen again.
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Message 1900038 - Posted: 9 Nov 2017, 16:37:21 UTC

So far Einstein is right.
General Relativity predicts that clocks go slower in a higher gravitational field. That is the clock aboard the GPS satellites "clicks" faster than the clock down on Earth.
Also, Special Relativity predicts that a moving clock is slower than the stationary one. So this effect will slow the clock compared to the one down on Earth.
If one does not compensate for the different clock speeds, the distance measurement would be wrong and the position estimation could be hundreds or thousands of meters or more off per day, making the GPS system essentially useless.

GPS satellite clocks gets ahead of the earth clocks by about 45 microseconds per day.
This means, if we do not factor in the time dilation, you'll get the distance to the satellites right on the first day, wrong by 13.5km the second day, 27 on the third day and so on.
https://www.quora.com/How-exactly-do-GPS-satellites-compensate-for-time-dilation-relative-to-the-earth-How-exactly-does-it-occur-How-significant-is-it
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Message 1900097 - Posted: 9 Nov 2017, 23:22:35 UTC - in response to Message 1899965.  

The thing most don't get is why time seems faster as you are heading to something. That is because you are overtaking the past. At your place you can only know about something after a photon takes a trip from the place it happened to you. So as you close the distance towards the source you run into the photons sooner than if you stayed put. This usually is thought of as the pitch of a train whistle or the Doppler effect. So red light is now blue. But red is the frequency or how many ticks of the light clock, blue is more ticks of the clock (as timed by your clock)

The Doppler effect makes sense to me because I've experienced it, but turning that into an understanding of why a speed of light Alpha Centauri trip would look longer to those on earth than me is still out of my grasp.


Sitting still you see the photon has a distance between the mirrors to go. As the you and the clock move faster the photon has to travel the distance between the mirrors and the distance forward you have gone. So the ticks are now farther apart. Most people understand that.

That sort of makes sense - That the photon of light has to travel further to get back to point A because you're still in motion, but the clock at point A is ticking the same way as the clock at point B(me), isn't it? What I mean is, if I looked at the clock in my super fast traveling spaceship, the second hand would still be moving at the same pace as the second hand of a clock on earth, right? If not, that is where my misunderstanding takes place.

Yes/no. Because of the speed of light, you can't be in both places to check both clocks at the same time. That's what sending each other messages at one year intervals is all about. (Replace the second hand with a light that flashes.) One year passes on earth, message sent*. Person on spaceship can't suddenly go back to earth to check the clock, he has to wait for news of the clock, the message or light flash, to arrive. He sees earth's clock slow, or red shifted. On the return trip he sees earth clocks as fast. Now from earth, it takes news that the spaceship is coming back a while to arrive. Until then earth sees the space clock as slow. This is where the earth ages and the spaceman doesn't.

For our triangle drawing, earth's path through spacetime is a straight line down. Our spaceship travels on two different straight lines. As the end points match, we have a big triangle. Earth's path is the hypotenuse and the spaceship the legs of the triangle. The spaceship can't take the same path back as it took out. Spacetime doesn't work that way because time is one way only.



*Using years, light years etc. just to keep the units the same.
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Message 1900429 - Posted: 11 Nov 2017, 2:05:29 UTC - in response to Message 1900097.  

Because of the speed of light, you can't be in both places to check both clocks at the same time. That's what sending each other messages at one year intervals is all about. (Replace the second hand with a light that flashes.) One year passes on earth, message sent*. Person on spaceship can't suddenly go back to earth to check the clock, he has to wait for news of the clock, the message or light flash, to arrive. He sees earth's clock slow, or red shifted. On the return trip he sees earth clocks as fast. Now from earth, it takes news that the spaceship is coming back a while to arrive. Until then earth sees the space clock as slow. This is where the earth ages and the spaceman doesn't.

I feel like the explanation seems to be mostly about individual perception and semantics. I still don't understand the difference between the spaceship clock and the earth clock. In my mind, if both are the same type of clock, the same amount of time should pass wherever they are sitting, regardless of how fast they are moving through the environment.
The mind is a weird and mysterious place
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Message 1900440 - Posted: 11 Nov 2017, 2:31:31 UTC - in response to Message 1899962.  

You aren't the only one posting a hypothesis here

Bob there is a difference between an hypothesis and a theory. An hypothesis is speculation, a theory requires some evidence. LIGO provided concrete evidence.
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Message 1900448 - Posted: 11 Nov 2017, 3:44:12 UTC - in response to Message 1900429.  

Because of the speed of light, you can't be in both places to check both clocks at the same time. That's what sending each other messages at one year intervals is all about. (Replace the second hand with a light that flashes.) One year passes on earth, message sent*. Person on spaceship can't suddenly go back to earth to check the clock, he has to wait for news of the clock, the message or light flash, to arrive. He sees earth's clock slow, or red shifted. On the return trip he sees earth clocks as fast. Now from earth, it takes news that the spaceship is coming back a while to arrive. Until then earth sees the space clock as slow. This is where the earth ages and the spaceman doesn't.

I feel like the explanation seems to be mostly about individual perception and semantics. I still don't understand the difference between the spaceship clock and the earth clock. In my mind, if both are the same type of clock, the same amount of time should pass wherever they are sitting, regardless of how fast they are moving through the environment.


A second is not the same for every observer. Time is not a constant value but a perception based upon the speed you are moving through space. The faster you are moving, the slower time goes because you are able "do" more in a second than someone moving slower than you.

For a different example, think back to the movie The Matrix, when Neo was on top the roof and he started shooting at an Agent, the Agent was moving so fast the bullets couldn't hit him because he was able to dodge them. Then the Agent returned fire on Neo and we saw time slow down as Neo dodged the bullets. From Neo's point of view, he could see the bullets moving toward him and he had enough time to react and move. From Trinity's point of view, Neo was moving so fast that he looked just like the Agent did moments prior. These are examples of time moving slower to the faster observer, as each observer was able to fit more into a second of time.
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Message 1900458 - Posted: 11 Nov 2017, 4:24:43 UTC - in response to Message 1900448.  

Time is not a constant value but a perception based upon the speed you are moving through space

That's exactly where I have trouble understanding things. I don't disagree with the math on paper, or the reality in proof, but the idea that a second in time is different depending on how fast you are traveling still hurts my head.
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Message 1900487 - Posted: 11 Nov 2017, 6:23:25 UTC - in response to Message 1900458.  

Would it help to think about it like this:

You've been trained to think of a second as saying to yourself "one, one thousand", right? So, imagine you're Trinity watching Neo dodging bullets and say to yourself, "one, one thousand." Look at how fast Neo was able to move when you said that. Now, imagine you're Neo and you're the one dodging bullets flying at your head and say to yourself, "one, one thousand." Same slice of time. Two different perspectives. The faster you are moving, the slower everything else around you appears in the same frame of time.

If you remained stationary but "operated"/moved at the speed of light, you would literally see people age before your eyes. In just under 2 and a half months, you would watch people age 70 years. In two of your years, 707 years of Earth time would pass. This is all possible because you're moving so much faster than everything around you. Your frame of reference; your perspective on time is different.
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Message 1900522 - Posted: 11 Nov 2017, 14:08:18 UTC

Wow. We did start talking about of the Universe and now talking relativity, time and quantum physics.
How many of you are physical?
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Message 1900528 - Posted: 11 Nov 2017, 14:55:54 UTC - in response to Message 1900522.  
Last modified: 11 Nov 2017, 15:03:48 UTC

Wow. We did start talking about of the Universe and now talking relativity, time and quantum physics.
How many of you are physical?

The topic of this thread is "The Universe" which means that you can discuss about everything:)
But I/we think that you mean discussions about science that is not terrestrial.
Quantum physics is both terrestrial and universal and I think it could be discussed here as well.

As for the question "How many of you are physical?"
We all are :)

And for all of us that quite not really grasps the science.
Don't worry. Most scientists dont that either.
"If I could explain it to the average person, it wouldn't have been worth the Nobel prize."
Richard Feyman.

Ciao.
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Message 1900529 - Posted: 11 Nov 2017, 15:15:43 UTC - in response to Message 1900528.  

Wow. We did start talking about of the Universe and now talking relativity, time and quantum physics.
How many of you are physical?

The topic of this thread is "The Universe" which means that you can discuss about everything:)
But I/we think that you mean discussions about science that is not terrestrial.
Quantum physics is both terrestrial and universal and I think it could be discussed here as well.

As for the question "How many of you are physical?"
We all are :)

Ciao.


I thought most of the users were just physical enthusiasts. I do not doubt that there are even physicists but I'm not.
When I asked the answers about the Universe, I read every single reply.
Just that I did not think of starting a discussion among experts.
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Message 1900530 - Posted: 11 Nov 2017, 15:18:41 UTC - in response to Message 1900429.  
Last modified: 11 Nov 2017, 15:44:40 UTC

Because of the speed of light, you can't be in both places to check both clocks at the same time. That's what sending each other messages at one year intervals is all about. (Replace the second hand with a light that flashes.) One year passes on earth, message sent*. Person on spaceship can't suddenly go back to earth to check the clock, he has to wait for news of the clock, the message or light flash, to arrive. He sees earth's clock slow, or red shifted. On the return trip he sees earth clocks as fast. Now from earth, it takes news that the spaceship is coming back a while to arrive. Until then earth sees the space clock as slow. This is where the earth ages and the spaceman doesn't.

I feel like the explanation seems to be mostly about individual perception and semantics. I still don't understand the difference between the spaceship clock and the earth clock. In my mind, if both are the same type of clock, the same amount of time should pass wherever they are sitting, regardless of how fast they are moving through the environment.
There is a reason it is called a light year. Time is actually in units of distance. We just find minutes a more convenient scale factor. I know that doesn't help. We are moving through spacetime at c. We mostly move through spacetime in the direction of time. Light moves through spacetime in the space direction and not in the time direction. As we move faster through spacetime in the space direction we must move slower in the time direction or we would go faster than c. All this adds up to the time dilatation effect. Yardsticks also are affected and a moving yardstick isn't the same length as a stationary one. But no surprise there, time is in units of distance.

Perhaps the light clock can get the idea across. Two mirrors one photon. Clock puts out a tick every time the photon hits a mirror. Sitting "at rest" the photon flies back and forth between the mirrors at c and the clock tick off the usual ticks. We launch the clock and now it is moving quickly. The photon can't go any faster than c. Because the clock is moving the photon is now going forward as well as bouncing between the mirrors. It is a longer path. Clock ticks slower. Speed the clock up to c, and the photon can't hit the mirrors any more as all its speed is used up staying in place in the clock, time stops. If you are along for the ride with the clock you have the same things happen to you. So to you the clock always ticks off time at exactly the same rate, because you don't notice any difference. It is only a different observer that can tell the change. Relative to the observer. Relativity.
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Message 1900539 - Posted: 11 Nov 2017, 16:40:31 UTC
Last modified: 11 Nov 2017, 16:52:37 UTC

There is also the problem to know what time is.
Gary said "Time is actually in units of distance" which is very true.
The differences between the three spatial dimensions and time is however that you cannot travel back in time.
Arrow of Time as it called.
https://www.youtube.com/watch?v=91RHD0RSRxY

And how about asking a scientist "What is the present time?"
No one can answer that question.

Oh. The event horizon of Black Holes.
To us observers it looks like that time are not moving at all there.
https://www.youtube.com/watch?v=mht-1c4wc0Q
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Message 1900547 - Posted: 11 Nov 2017, 17:38:20 UTC

I have another question:

Based on the Kardashev scale, an ipotetic alien civilization is capable of manipulating the structure of Universe.
Type V is capable of manipulating the atomic nucleus and engineering the nucleons that compose it.

The type VI is capable of manipulating the most elementary particles of matter (quarks and leptons) to create organized complexity among populations of elementary particles; culminating in;

Type Omega is capable of manipulating the basic structure of space and time.

This imply that they are capable of traveling over time and capable to map the entire Universe.
They should know if existing more civilization and in which point.
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Message 1900548 - Posted: 11 Nov 2017, 17:38:28 UTC

I have another question:

Based on the Kardashev scale, an ipotetic alien civilization is capable of manipulating the structure of Universe.
Type V is capable of manipulating the atomic nucleus and engineering the nucleons that compose it.

The type VI is capable of manipulating the most elementary particles of matter (quarks and leptons) to create organized complexity among populations of elementary particles; culminating in;

Type Omega is capable of manipulating the basic structure of space and time.

This imply that they are capable of traveling over time and capable to map the entire Universe.
They should know if existing more civilization and in which point.
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Message 1900567 - Posted: 11 Nov 2017, 19:09:32 UTC - in response to Message 1900547.  

Sorry, I'm not seeing a clear question in there. Can you clarify what your question is?
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