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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 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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Message 1900739 - Posted: 12 Nov 2017, 18:01:09 UTC - in response to Message 1900734.  
Last modified: 12 Nov 2017, 18:02:38 UTC

Damn it! A lot of variable. It's unnerving living with this doubt.
I'll look stubborn or stupid but I would like to know if someone there listening to us and returning at least with a ''Hey we are here''.

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?

Even more depressing :(

If the SETI listening but they do not want to be heard, you think this could be a possibility or a paradox?
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Message 1900743 - Posted: 12 Nov 2017, 18:36:16 UTC - in response to Message 1900739.  

Rather than fill your mind with doubt and your emotions with depression, look to all the wonder and mystery the Universe has to offer! I'm excited to think that if we strive hard enough, and we act intelligently enough, we might be able to answer some or all of those questions.

If the SETI listening but they do not want to be heard, you think this could be a possibility or a paradox?


I think it's a Schrodinger's Cat kind of situation whereupon we can't know the answer because we haven't opened the box. It is both equally possible that they are listening and don't want to be heard, and it's possible they are broadcasting and want to be heard. Given a populous Universe, one civilization might take the former philosophy while another may take the latter. It would be foolish and rather binary to think that either all civilizations are listening and don't want to be heard, or they are all broadcasting and want to be heard. The binary scenarios have their probabilities of being true, of course, but I don't put much weight into the thought that no one wants to be heard.

Regardless of which probability is more accurate, I think searching for answers is the only way to gain a better understanding.
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Message 1900793 - Posted: 12 Nov 2017, 22:55:13 UTC - in response to Message 1900743.  

Regardless of which probability is more accurate, I think searching for answers is the only way to gain a better understanding.

Yes, indeed.
So far we, SETI, only search for carrier waves that perhaps other intelligente beings are used to transfer informtion
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Message 1900831 - Posted: 13 Nov 2017, 5:18:19 UTC - in response to Message 1900530.  

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.

I can follow that.
It is a longer path.
Clock ticks slower.

I follow the longer path concept, but I still don't see how that means clocks in two different places literally tick more slowly.
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.

You lose me here. I think part of the problem is I see clocks and photons as acting independently of each other; i.e., they don't know each other exists.
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.

Time is ticking off for me at one rate and for my friends at another rate?
The mind is a weird and mysterious place
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Message 1900837 - Posted: 13 Nov 2017, 6:39:21 UTC - in response to Message 1900831.  

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.

I can follow that.
It is a longer path.
Clock ticks slower.

I follow the longer path concept, but I still don't see how that means clocks in two different places literally tick more slowly.
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.

You lose me here. I think part of the problem is I see clocks and photons as acting independently of each other; i.e., they don't know each other exists.

Remember time is measured in units of distance. Give a distance of 9.461e+12Km and a photon makes the trip in what we call a year. The photon has to be able to hit a mirror for there to be a tick on the clock. No ticks = time stops. Perhaps you do understand the farther we look out into space the farther back in time we look in time. That is because the photon we see has been frozen in time and the distance it travels is how much back we are looking.
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.

Time is ticking off for me at one rate and for my friends at another rate?
Precisely. And if you are close enough to compare clocks, say GPS satellites you will note that their clocks tick at a different rate than the clock you have. It is all a bit weird but is all comes from the speed of light being the same for every observer. Something has to change for that to be true. Rate time passes is a thing that changes.
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Message 1900841 - Posted: 13 Nov 2017, 6:56:27 UTC - in response to Message 1900837.  

Let's not forget what these monsters can do with time.

According to Einstein's theory of general relativity, massive objects create distortions in space and time. ... It never crosses the event horizon, but stays frozen there in space and time. The falling clock also becomes continuously redder, since its light loses energy as it escapes from the black hole's vicinity.
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Message 1900863 - Posted: 13 Nov 2017, 9:26:41 UTC - in response to Message 1900831.  

Time is ticking off for me at one rate and for my friends at another rate?

Yes. Every object in the Universe "lives" in their own time that is a position in the space-time reality.
As much an object cannot exist in the same spatial location with an other object they cannot exist in the same position in time either.
What is Time?
https://www.youtube.com/watch?v=91RHD0RSRxY
The Times They Are A Changin'
https://www.youtube.com/watch?v=e7qQ6_RV4VQ
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Message 1900864 - Posted: 13 Nov 2017, 9:52:22 UTC - in response to Message 1900841.  

Let's not forget what these monsters can do with time.

According to Einstein's theory of general relativity, massive objects create distortions in space and time. ... It never crosses the event horizon, but stays frozen there in space and time. The falling clock also becomes continuously redder, since its light loses energy as it escapes from the black hole's vicinity.

Mindgobbling:)
It never crosses the event horizon, but stays frozen there in space and time.

Actually it's the information of objects falling into a massive object horizon of events to us observers that to us looks like the time stand still.
As for the object itself time will pass as always.
Until you get spaghettified of course:)


https://en.wikipedia.org/wiki/Information_theory
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Message 1900870 - Posted: 13 Nov 2017, 11:15:07 UTC - in response to Message 1900867.  

We don't even really know what reality is.
Scientists usually start to giggle when asked:)
http://www.dailymotion.com/video/x21ss62
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Message 1900876 - Posted: 13 Nov 2017, 13:11:06 UTC

Could an astronaut die if he is too close to the black hole? And what is sucked into the black hole, comes out of a white hole? Or is it transformed into '' other ''?
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Message 1900881 - Posted: 13 Nov 2017, 13:42:00 UTC - in response to Message 1900878.  
Last modified: 13 Nov 2017, 13:44:54 UTC

I think you need to read up on black holes Andrew!!

A black hole is a place in space where gravity pulls so much that even light can not get out. The gravity is so strong because matter has been squeezed into a tiny space.
Of course an astronaut would die!!

Black holes into white holes??? Are you getting confused with wormholes? Like them white holes are purely theoretical.

Black holes

White holes


Hi Chris.
White Hole
What is a Whith Hole?

I mean if the astronaut approach a black hole he would die instant.
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Message 1900891 - Posted: 13 Nov 2017, 14:58:47 UTC - in response to Message 1900876.  
Last modified: 13 Nov 2017, 15:13:20 UTC

Could an astronaut die if he is too close to the black hole? And what is sucked into the black hole, comes out of a white hole? Or is it transformed into '' other ''?

First question: No, the astronaut experience the same laws of natures as we all do.
Second question:The information of the objects stay in the event horizon when falling in.
The matter however that fall in are converted to pure energy and "disappear'' in the center.
There is a misconseption about this and the fact is actually is that matter converts to pure energy making the space around it to become distorted.
These findings are not theoris and are an observable fact.
There is no mass in a black hole, only energy that make the surrounding prone to gravity.
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Message 1900902 - Posted: 13 Nov 2017, 16:02:55 UTC - in response to Message 1900899.  

An Event Horizon is simply a posh term for a point of no return.

What? Posh term?
Since when is a scientific term called "posh"?
As for Event Horizons that are real and not posh at all, we all know that they are the end of line in our universe.
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