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OzzFan
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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 1900489 - Posted: 11 Nov 2017, 6:45:15 UTC

I have to agree with Gordon, I accept that things are apparently as they are, but I don't fully understand it, and am not inclined to bend my brain when I don't need to, either for a living or indeed a hobby.

It all reminds me of the old conundrum where you have a train at 100mph going round a curve the Guard in the van at the back has a rifle that can fire a bullet at 100mph. Can he hit the driver?

There is a difference between an hypothesis and a theory
My ideas of the universe are neither. I don't have any evidence, and neither any background to base an informed speculation on. I have simply put forward a possible explanation of the phenomena that we see. There is no way of knowing if it is right or wrong or wildly off beam. It simply ticks a few boxes for me personally.
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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 1900523 - Posted: 11 Nov 2017, 14:26:01 UTC

I'm just a figment of my own imagination. The others may be holograms.
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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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Message 1900593 - Posted: 11 Nov 2017, 21:12:30 UTC

It predicts that mankind won't even reach Type 1 until 200 years from now, so it seems rather pointless to consider it all really.
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Message 1900663 - Posted: 12 Nov 2017, 7:43:32 UTC - in response to Message 1900567.  

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



@OzzFan

Sorry, I forgot to ask the question.

The question is: an ipotetic alien civilization could modify the Universe, time and space? If yes, could it have any repercussions on our reality as
well? If they have the technology for receive our signal transmission from SETI, why don't they contact us or come here? If they are capable to travel at the speed of light or through wormhole, why don't they come here?
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Message 1900665 - Posted: 12 Nov 2017, 7:50:49 UTC - in response to Message 1900593.  
Last modified: 12 Nov 2017, 7:50:57 UTC

It predicts that mankind won't even reach Type 1 until 200 years from now, so it seems rather pointless to consider it all really.


@Chris S

This doesn't would exclude if exists a very advanced civilization and come on the Earth. Maybe they do not want to interfere with our evolution, but they could also serve as an objective to help others sentient beings to grows.
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Message 1900671 - Posted: 12 Nov 2017, 8:21:49 UTC - in response to Message 1900663.  

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

@OzzFan
Sorry, I forgot to ask the question.
The question is: an ipotetic alien civilization could modify the Universe, time and space? If yes, could it have any repercussions on our reality as
well? If they have the technology for receive our signal transmission from SETI, why don't they contact us or come here? If they are capable to travel at the speed of light or through wormhole, why don't they come here?

I guess that you mean hypothetical aliens.
Enrico Fermi said "Where is everybody"

I wonder too.
https://en.wikipedia.org/wiki/Fermi_paradox
Ciao:)
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Message 1900673 - Posted: 12 Nov 2017, 8:34:00 UTC - in response to Message 1900671.  

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

@OzzFan
Sorry, I forgot to ask the question.
The question is: an ipotetic alien civilization could modify the Universe, time and space? If yes, could it have any repercussions on our reality as
well? If they have the technology for receive our signal transmission from SETI, why don't they contact us or come here? If they are capable to travel at the speed of light or through wormhole, why don't they come here?

I guess that you mean hypothetical aliens.
Enrico Fermi said "Where is everybody"

I wonder too.
https://en.wikipedia.org/wiki/Fermi_paradox
Ciao:)


I have heard on television that scientists assume that these civilizations might have disappeared, either because of a devastating war or simply extinct.
In addition to Enrico Fermi's paradox I like to cite too quote from Arthur C. Clarke: “Two possibilities exist: either we are alone in the Universe or we are not. Both are equally terrifying.”
Clarke was afraid of a possible aggressive and conquering civilization. In fact, he does not have all the wrongs. But I believe there are also peaceful civilizations.

Ciao moomin. :)
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Message 1900676 - Posted: 12 Nov 2017, 9:03:44 UTC
Last modified: 12 Nov 2017, 9:09:16 UTC

Fermi's paradox, named after physicist Enrico Fermi, is the apparent contradiction between the lack of evidence and high probability estimates for the existence of extraterrestrial civilizations. The basic points of the argument, made by physicists Enrico Fermi (1901–1954) and Michael H. Hart (born 1932), are:

    1. There are billions of stars in the galaxy that are similar to the Sun, many of which are billions of years older than Earth.

    2. With high probability, some of these stars will have Earth-like planets, and if the Earth is typical, some might develop intelligent life.

    3. Some of these civilizations might develop interstellar travel, a step the Earth is investigating now. (is it?)

    4. Even at the slow pace of currently envisioned interstellar travel, the Milky Way galaxy could be completely traversed in a few million years.


According to this line of reasoning, the Earth should have already been visited by extraterrestrial aliens.

There are simply too many unknowns there for any of that to hold water. And the biggest problem is the sheer distances of interstellar space which weren't factored in. All Fermi did was use a collection of positives in place of where there were possibles or maybes, and came up with a possible scenario which even then couldn't be proved for a few million years. Few million? how many is a few 5, 20, 100?

He knew he couldn't be proved right or wrong, so why not chuck it into the mix. It is not a scientific paradox at all, just someone posing a question after musing upon known facts of the time in 1950 (Apparently during a lunch).

Wiki site.

Fermi

p.s. Seti is NOT sending OUT signals of its own it is looking for signals coming IN from others.

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Message 1900679 - Posted: 12 Nov 2017, 9:16:49 UTC - in response to Message 1900676.  
Last modified: 12 Nov 2017, 9:23:34 UTC

Fermi's paradox, named after physicist Enrico Fermi, is the apparent contradiction between the lack of evidence and high probability estimates for the existence of extraterrestrial civilizations. The basic points of the argument, made by physicists Enrico Fermi (1901–1954) and Michael H. Hart (born 1932), are:

    1. There are billions of stars in the galaxy that are similar to the Sun, many of which are billions of years older than Earth.

    2. With high probability, some of these stars will have Earth-like planets, and if the Earth is typical, some might develop intelligent life.

    3. Some of these civilizations mightdevelop interstellar travel, a step the Earth is investigating now.

    4. Even at the slow pace of currently envisioned interstellar travel, the Milky Way galaxy could be completely traversed in a few million years.


According to this line of reasoning, the Earth should have already been visited by extraterrestrial aliens.

There are simply too many unknowns there for any of that to hold water. And the biggest problem is the sheer distances of interstellar space which weren't factored in. All Fermi did was use a collection of positives in place of where there were possibles or maybes, and came up with a possible scenario which even then couldn't be proved for a few million years. Few million? how many is a few 5, 20, 100?

He knew he couldn't be proved right or wrong, so why not chuck it into the mix. It is not a scientific paradox at all, just someone posing a question after musing upon known facts of the time in 1950 (Apparently during a lunch).

Wiki site.

Fermi

p.s. Seti is NOT sending OUT signals of its own it is looking for signals coming IN from others.



We take for granted that there are other forms of life in the Universe seen its vastness. Now, some this civilization should have could a different evolutionary path from ours.
Given that they are really advanced, given that they are able to travel in space, assuming they have the technology to use shortcuts to shorten the distance from point A to point B, this should not increase the chances, albeit low, of their contact with us?

Really, i don't understand why this Universe are really very big and so little '' inhabited ''.

Wait: SETI not sendig out signals WHILE receiving?

Edit: Crap. I confused with Arecibo message -.-'' Shame on me.
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Message 1900682 - Posted: 12 Nov 2017, 10:09:23 UTC

If existing the Stargate.
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Message 1900734 - Posted: 12 Nov 2017, 17:11:08 UTC - in response to Message 1900663.  
Last modified: 12 Nov 2017, 17:13:41 UTC

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



@OzzFan

Sorry, I forgot to ask the question.

The question is: an ipotetic alien civilization could modify the Universe, time and space? If yes, could it have any repercussions on our reality as
well? If they have the technology for receive our signal transmission from SETI, why don't they contact us or come here? If they are capable to travel at the speed of light or through wormhole, why don't they come here?


Doesn't that presuppose that such an advanced civilization exists? Further, doesn't that presume the Kardashev scale, which is arbitrary in its classifications, based purely on hypothetical advancements and fictional evolutionary landmarks, is even remotely correct?

The Kardashev scale is fun to talk about and consider, however I think it is premature to start drawing inferences or conclusions from such a scale. I've written previously that we have no actual basis or reference as to when an advanced civilization is supposed to appear in a given lifetime of a Universe (and yes, that statement presupposes a theoretical multiverse).

Before we can point to the age of our Universe and say "there should have been an advanced civilization by now!" we must first consider we do not have any reference data to draw from. For example, we estimate our Universe to be 13.8 billion years old. Is this a young Universe? Middle-aged Universe? Are we an old Universe? Whatever answer you choose for each of those question, follow up each with: At what point should intelligent life develop? How quickly should an advanced civilization develop? How long before a civilization becomes a Type III on the Kardashev scale?

If we are a young Universe, there simply may not have been time for such a civilization to evolve. If we are a middle-aged Universe, there may be civilizations on the cusp of such an advancement and may need a few hundred thousand more years. If we are an old Universe, then your questions are worth additional consideration, and perhaps the validity or the feasibility of the Kardashev scale might be called into question.

Assuming you follow the mainstream scientific point of view that we have not yet to our knoweldge been visited by alien life forms, there are additional questions and considerations to think about before making further assumptions, each acknolwedging our lack of data. For example, what if we are actually alone? What if we are the first civlization to advance (assuming a young Universe hypothesis)? What if other civilizations have destroyed themselves before ever reaching the prestige of Type III? What if, by nature of the makeup of our existence, humanoid lifeforms are not able to exist beyond a few million years before the next catastrophic extinction event occurs? What if such advanced civilizations have their version of the Star Trek Prime Directive to not get involved in a civilization until they've reached a certain point in their advancement?

So you see, before we start jumping to conclusions about "where are they and why haven't they ran the front door bell?" we need to consider and temper our expectations in the face of lack of additional reference data.
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