BF2S Forums D&ST - Science

Cheeky_Ninja06 wrote:

Kmar wrote:

It's really easy to say, "holy hell that's a lot of Universe, and therefor there must be some intelligent life out there". But in a sea of endless possibilities "100 million light years away" really isn't a big hurdle. Like the man said, just being far away is not enough to explain away contact. Especially, if you believe the universe to be infinite, you would have an infinite number of alien civilizations. The fermi paradox is simply asking a question. Attempting to solve that paradox is where it gets interesting. I believe the evolution of intelligent life is very rare, and that would answer the question. Just because we see it here it doesn't mean it is happening all over the place (See Observation Selection effect in the video). Other explanations are that maybe earth is intentionally isolated and we are in a zoo like environment, forbidden from interactions (insert star trek prime directive here). Maybe intelligent life is more common than we know and it is just destined to destroy itself or be destroyed by something else, like the dinosaurs (IE great filter).

100 million light years may not be a big hurdle to a potential form of intelligent life but to us it means we are looking at what happened 100 million years ago, not what is currently happening. That was the point I was making its not so much the distance that is the problem but the issue of the further afield we look the further back in time we go. Hence as distance increases we are proportionally less likely to find evidence of life.


Its difficult to figure out how we get around that.

The Fermi paradox is a conflict between an argument of scale and probability and a lack of evidence. A more complete definition could be stated thus:

    The apparent size and age of the universe suggest that many technologically advanced extraterrestrial civilizations ought to exist.
    However, this hypothesis seems inconsistent with the lack of observational evidence to support it.

The first aspect of the paradox, "the argument by scale", is a function of the raw numbers involved: there are an estimated 200–400 billion (2–4 ×1011) stars in the Milky Way and 70 sextillion (7×1022) in the visible universe.[10] Even if intelligent life occurs on only a minuscule percentage of planets around these stars, there might still be a great number of civilizations extant in the Milky Way galaxy alone. This argument also assumes the mediocrity principle, which states that Earth is not special, but merely a typical planet, subject to the same laws, effects, and likely outcomes as any other world.

The second cornerstone of the Fermi paradox is a rejoinder to the argument by scale: given intelligent life's ability to overcome scarcity, and its tendency to colonize new habitats, it seems likely that at least some civilizations would be technologically advanced, seek out new resources in space and then colonize first their own star system and subsequently the surrounding star systems. Since there is no conclusive or certifiable evidence on Earth or elsewhere in the known universe of other intelligent life after 13.7 billion years of the universe's history, we have the conflict requiring a resolution. Some examples of which may be that intelligent life is rarer than we think, or that our assumptions about the general behavior of intelligent species are flawed.

The Fermi paradox can be asked in two ways. The first is, "Why are no aliens or their artifacts physically here?" If interstellar travel is possible, even the "slow" kind nearly within the reach of Earth technology, then it would only take from 5 million to 50 million years to colonize the galaxy.[11] This is a relatively small amount of time on a geological scale, let alone a cosmological one. Since there are many stars older than the Sun, or since intelligent life might have evolved earlier elsewhere, the question then becomes why the galaxy has not been colonized already. Even if colonization is impractical or undesirable to all alien civilizations, large-scale exploration of the galaxy is still possible; the means of exploration and theoretical probes involved are discussed extensively below. However, no signs of either colonization or exploration have been generally acknowledged.

The argument above may not hold for the universe as a whole, since travel times may well explain the lack of physical presence on Earth of alien inhabitants of far away galaxies. However, the question then becomes "Why do we see no signs of intelligent life?" since a sufficiently advanced civilization[Note 1] could potentially be observable over a significant fraction of the size of the observable universe. Even if such civilizations are rare, the scale argument indicates they should exist somewhere at some point during the history of the universe, and since they could be detected from far away over a considerable period of time, many more potential sites for their origin are within range of our observation. However, no incontrovertible signs of such civilizations have been detected.

Cheeky_Ninja06 wrote:

Kmar wrote:

Spark wrote:

First we have to decide what life is. What if the plasma computational models from a few years ago are potentially illuminating, and large pockets of intersellar plasma can organize themselves into structures that behave precisely like life?

The sun is life.. we're parasites. There is a reason they call it life "as we know it". It's because it is all relative. Anyone who has seen 2001: A Space Odyssey knows that we will eventually evolve into star children, returning to our roots. We are here occupying an immeasurable amount of time, in an attempt for the universe to explain and understand itself. .. now pass the pipe.

I would leave life as something very basic along the lines of reproductive and self sustaining, i.e. no need for a 3rd party to control or influence them. But even then you could arguably have life that doesnt obey that.

FatherTed wrote:

FatherTed wrote:

http://www.bbc.co.uk/news/science-environment-15017484

light speed barrier maybe broken at cern O:

OH FUCK YOU RTHKI

Last edited by Spark (2011-10-04 03:22:21)

Light speed, or 300,000 kilometers a second, might seem like a speed limit, but this is just an example of 3 + 1 thinking – where we still haven’t got our heads around the concept of four dimensional space-time and hence we think in terms of space having three dimensions and think of time as something different.

...

Speed is just a measure of how long it takes you reach a distant point. Relativity physics lets you pick any destination you like in the universe – and with the right technology you can reduce your travel time to that destination to any extent you like – as long as your travel time stays above zero.

That is the only limit the universe really imposes on us – and it’s as much about logic and causality as it is about physics. You can travel through space-time in various ways to reduce your travel time between points A and B – and you can do this up until you almost move between those points instantaneously. But you can’t do it faster than instantaneously because you would arrive at B before you had even left A.