Parallel Universes

The non amateur stuff. Hawking, black holes, that sort of thing

Moderators: joe, Brian, Guy Fennimore

davep
Posts: 2814
Joined: Fri May 06, 2005 11:07 am
Location: South Lincolnshire
Contact:

Post by davep »

Cliff wrote:Taking an extreme case could the rocket crew mutiny when they land and never take off back homewards.
That doesn't make a difference to what Joe said. It's the same thing, it's just that -- in time -- there's a different outcome. Joe's point wasn't that they'd head back, Joe's point was that whatever they do, for us observing them, the outcome is already decided.
joe
Site Admin
Posts: 4382
Joined: Fri Dec 03, 2004 11:24 am
Location: Greenwich, London
Contact:

Post by joe »

Hi Cliff,

Yes, I was trying to point, out once again I'm afraid, that our view of the universe is necessarily one that is based on slow speeds, short distances, relatively weak gravitational fields and for us, moderate temperatures. Our notion of time has been developed within these parameters and once we break out of them we have to think differently. As regards to the rocket it was simply that as we see the rocket reach the star, no matter what it does afterwards, it has already been done.

To ask whether all of time is already "out there" is an interesting question and one that can be taken seriously. The example I tried to convey was to illustrate that at least for that journey and those protagonists, part of their life was predetermined and "out there" and there was nothing they could do about it. A timespan of about ten or fifteen years existed at one "moment" and it has to be said it seemed as if they had free choice.

Now, if the universe was completely static there would be no time. Time is a measure of change and a static universe does not change. We have seen with the above example that a movement, seperation or large change in velocity resulted in a period whereby everything was predetermined. Think now of this static universe, if it now for some reason begins to move or change we would have to have the introduction of time but could it be that ALL of the movement or change that the universe undergoes is exactly like the above example (an extreme example to illustrate a point) and from any personal point of view all of time is already "out there"? And to put a familiar name to all this we know that the Big Bang was the beginning of all movement and time.

Quantum Mechanics muddies the water a bit hence the lack of a theory relating gravity to QM.
200mm Newtonian, OMC140, ETX90, 15x70 Binoculars.
Cliff
Posts: 6600
Joined: Sat Dec 11, 2004 8:18 pm
Location: Manchester
Contact:

Post by Cliff »

Dear Joe and davep
I think (and indeed thought before this) that I agree with you. My mutiny nonsensical point was mentioned hoping to confirm that I was understanding what you meant. I think that is OK.
However, I am a bit bugged by this "faster than light" possibility or impossibility?
I am an old fogie, and I have never really liked science fiction. To be honest "Doctor Who" is not really for me - and very particularly the new series. Peoples expectations these days are sort of wanting instant this,instant that. Computer games, unreality TV and special effects have a lot to answer for.
Whatever, I suppose I am sidetracking, and what I say now may have only tenuous connections with astronomy and even cosmology. However, I personally tend to be happy to accept that for all practical purposes, the speed of light is one speed limit humans are unlikely to ever beat. I think I am a fairly safe bet that will be the case in my lifetime ????
I suppose I am wittering on saying again, that if we accept intelligence involves decision making. Then decision making can never be done instantaneously. Even just one intelligent person needs time to weigh up a situation and then come to a decision - hopefully a good one. So even is two particles on opposite sides of the universe can instantaneously communicate with each other, the second particle could not instantaneously change the first particles decision on some issue.
If intelligent life could harness the power of intantaneous communication as the previously mentioned particles can acroos the Universe, then it would certainly speed up communications. At least on the face of it!
But I cannot help wondering if having supposed intelligence is a limiting factor in what we (humans or other life forms) can ever be capable of.
Perhaps only "lifeless" contraptions are capable of harnessing maximum quantum efficiency and life forms are governed by simple rules, such as the the speed of light speed limit?
Sorry if that is just a load of rubbish.
Best of luck from the Grumpy Old Codger Cliff
joe
Site Admin
Posts: 4382
Joined: Fri Dec 03, 2004 11:24 am
Location: Greenwich, London
Contact:

Post by joe »

Hi Cliff,

I think you are dead right about instantaneous decision making or rather the lack of it. In fact any conscious decision takes around a half of a second to complete but our brain fools us to make us think that it is much quicker. I remember being amazed to find out that our body uses about 1 million "Bits" or is it bytes of information each second. These are used to control our reflexes and instincts, etc. But our conscious mind uses only around a dozen bits per second!! This is all our mind needs to control oneself. Consciousness or intelligence is a very tenuous substance indeed.

But this is not astronomy and I now have to warn myself to stay on topic. :wink:

Regards,
200mm Newtonian, OMC140, ETX90, 15x70 Binoculars.
davep
Posts: 2814
Joined: Fri May 06, 2005 11:07 am
Location: South Lincolnshire
Contact:

Post by davep »

Cliff wrote:Perhaps only "lifeless" contraptions are capable of harnessing maximum quantum efficiency and life forms are governed by simple rules, such as the the speed of light speed limit?
That reminds me of an article I read some time back regarding quantum mechanics and its role in the "design" of living things. I can't for the life of me remember where I read it. I think it might have been in New Scientist. A search of their archives turns up this article (that only gives an introduction, the full article can only be read with a subscription) which sounds vaguely similar.
Cliff
Posts: 6600
Joined: Sat Dec 11, 2004 8:18 pm
Location: Manchester
Contact:

Post by Cliff »

Dear Joe and Davep
I must admit this topic surpisingly got me quite interested and very curious to find out more.
Joe is perhaps understandably concerned about the possibility of ramblig off topc. However, I personally am inclined to think that some astronomers are to gripped up about SETI which tends to frustrate me.
(No intention there of making a dig at anyone contributing to this chat by the way.)
I could be wrong of course but I think SETI research is a waste of time.
I have said much the same before so please excuse me wittering. Seti research may be worthwhile at some future time but not yet. The only thing I can say in its favour is hopefully professional Seti research will provide some useful spin-off. As far as I know humans, cannot yet really satisfactorily communicate with other animals on Earth. Once that problem has been overcome then it might be worth doing Seti research.
I can only think SETI is used a way of trying to get the public more interested in Astronomy and cosmology. Personally I find astronomy and cosmology interesting enough subjects without me needing SETI. Indeed I sometimes wonder if at some stage in future if SETI research does not turn up something really positive Joe Public will completely be turned off by the subject and want nothing to do with astronomy.
Well I am wittering again. However, our previous recent entertaining discussions have got me round to wondering if time is really only relavent to life and most particularly intelligent life. Could it be that intelligent life is really the least intelligent, or at least not as clever as it thinks it is?To be honest even though I say that I am not really sure what I am getting at -probably just rubbish.
I think Joe suggested something to the effect tha possily all time exists now. That got me wondering (hopefully my feelings about Joe's comments were right?).
Anyway it made me think that in a way, possibly more than one way, Joe could be right. That made me wonder at one particular instant does all of time (but only up to that particular instant exist). Perhaps at instant an hour later, all time exists covering an extra hour than the time before.
I assume "probably" the future is not included in all the time related to a particular instant, or is it?
Having said all that rubbish I hate to think I might be thinking like a scientific luddite. Perhaps I am getting out of my depth and should shut up.
Best wishes from the the Grumpy Old Codger (who may be loosing his marbles) Cliff
davep
Posts: 2814
Joined: Fri May 06, 2005 11:07 am
Location: South Lincolnshire
Contact:

Post by davep »

Cliff wrote:I could be wrong of course but I think SETI research is a waste of time.
Why?
Cliff wrote:As far as I know humans, cannot yet really satisfactorily communicate with other animals on Earth. Once that problem has been overcome then it might be worth doing Seti research.
How do you see communication as something linked with SETI? SETI is about a search, it isn't about communication. You don't need to have cracked the problem of communication with other lifeforms to do the bit about searching for ETI.
Cliff wrote:I can only think SETI is used a way of trying to get the public more interested in Astronomy and cosmology.
Is that really the only way you can think about it? Try this one: we know that life exists in the universe, we know that life exists in our own galaxy. We know that some of that life that exists in this galaxy has managed to reach a point where it's started to leak information out into the surrounding space -- for all intents and purpose, in the last 60+ years, we've been shining a lighthouse saying "here we are".

So, given that we know that much, doesn't it make some sense to ask the question "if we know this has happened once, could it be happening more than once?". It strikes me that this is a reasonable and sensible question. And, having asked that question, it seems reasonable and sensible to try and answer it and the first thing to do in trying to answer it is to look for evidence. SETI is a method of looking for that evidence.

Sure, it seems highly unlikley that we'll find the evidence, but if you don't look you'll never know.

No, I'm not at all sure that I can go along with the idea that SETI is just about getting the "general public" interested in astronomy; that might be a (welcome) side-effect but I can't see how it is the primary reason.
Asteeleleith
Posts: 171
Joined: Tue May 24, 2005 2:19 am
Location: Northampton
Contact:

Life in the unverse

Post by Asteeleleith »

Hi all
to comment on the above, i have to say and i know this is going to sound as ridiculous as my theory of parallel universes but.

I do not think the question should be, is there life in the universe, but where is it.

I am sure any ET's would be aware of our existance, and if they have travelled here to spy on us as some believe. Then these beings have learned to master space and time.

Best Regards

Alastair
Engineer, businessman, and Astronomer
davep
Posts: 2814
Joined: Fri May 06, 2005 11:07 am
Location: South Lincolnshire
Contact:

Re: Life in the unverse

Post by davep »

Asteeleleith wrote:I do not think the question should be, is there life in the universe, but where is it.
The odds do seem in favour of that view. But "if" rather than "where" is the better position to start from. That said, we know for sure that there is life in the Universe.
Asteeleleith wrote:I am sure any ET's would be aware of our existance,
Why? We are a lifeform in the Universe and we don't have this sort of knowledge. Assuming there are other civilisations out there, why are you sure they do? Are you sure just some of them do or all of them do?
Asteeleleith wrote:and if they have travelled here to spy on us as some believe. Then these beings have learned to master space and time.
Sadly that's a big if with no credible evidence.
Cliff
Posts: 6600
Joined: Sat Dec 11, 2004 8:18 pm
Location: Manchester
Contact:

Post by Cliff »

Dear Davep
In a funny way I actually agree with you disagreeing with me on these issues and in particular about SETI.
Firstly I have to admit that I am very prejudiced against SETI.
Although funnily enough I take a rather negative view about there being life in the universe (other than Earth that is). I do accept that it seems likely there is some sort of life elsewhere. However, having said that I personally do not think it worth the effort (at least at present) trying to find such life beyond Earth, because I do not think we are currently sufficiently advanced to find it.
Having said that I realise I could be eating my words, some experts reckoned heavier than air flight was impossible and a short time later the Wright brothers did it! And I am no expert on SETI so I could be talking rubbish!
However, I treat the current attitude to Seti rather like the Martian Canal furor at the end of the 19th start of the 20th century. Many people got totally gripped by the thought of life on Mars. It was only dispelled when Viking and wotnot revealed Mars for what it is. To me as an astronomical observer Mars is a fascinating thing to observe, possibly my favourite planet. I must admit the history of Mars observation interests me and adds spice to my observing. But I often think that the old dream continues, the desire to find life on Mars is still there. Even though now they realise that any Martian life still existing is likely to be be pretty puny.
I do not entirely agree wth you though that SETI is pure science. True as you say "if you do not look, you will never find". That is fair comment, to a point. But by the same token there are some people who ardently search for UFOs. As far as I am concerned they are doing no great harm, but what they do and even to a point stand for, is not for me.
Again I could be eating my words. Over the years I have done a fair bit of observing, even before I became a "real serious" astronomer. I have seen some fantastic things but I have never seen anything that I would consider to be a convential UFO. I am afraid as far as I am concerned SETI is almost in the UFO category.
I find astronomy fascinating enough in itself for me not to need UFOs or SETI.
Best wishes from the Grumpy Old Coger Cliff
joe
Site Admin
Posts: 4382
Joined: Fri Dec 03, 2004 11:24 am
Location: Greenwich, London
Contact:

Post by joe »

I'm sure the SETI people know exactly what they are doing and as I have not seriously looked at their website I may be talking out of some place other than my mouth but surely to goodness even if an exoplanet civilisation tried to contact us the chances or even the possibility of detecting a signal are vanishingly small. How much power is needed to send a signal that will be picked up 10 light years away? That is assuming that we are fortunate enough to have a lifeform so close to us that thought of such a thing. The issue of us having been broadcasting for the last 60-70 years, what state are those photons in now after having been dispersed for such a long time? This doesn't even mention the fact that out of the 4500000000 years of the lifetime of the Earth we have been in a position to receive transmissions for only 70 of them. What are the chances of two civilisations being able to broadcast and receive at the same minute fraction of the lifetime of their planets? This does not bring in also the hugely fortunate set of circumstances that allowed the evolution of intelligent life on this particular planet that we inhabit!
200mm Newtonian, OMC140, ETX90, 15x70 Binoculars.
davep
Posts: 2814
Joined: Fri May 06, 2005 11:07 am
Location: South Lincolnshire
Contact:

Post by davep »

Cliff wrote:Although funnily enough I take a rather negative view about there being life in the universe (other than Earth that is). I do accept that it seems likely there is some sort of life elsewhere.
What form does this negative view take and how do you reconcile it with your view that life elsewhere is likely?
Cliff wrote:However, having said that I personally do not think it worth the effort (at least at present) trying to find such life beyond Earth, because I do not think we are currently sufficiently advanced to find it.
What level of advancement do you think we need to conduct the search? Note that I'm talking about just the search here, not any attempt at actual communcation (something that has problems on many levels).
Cliff wrote:However, I treat the current attitude to Seti rather like the Martian Canal furor at the end of the 19th start of the 20th century. Many people got totally gripped by the thought of life on Mars. It was only dispelled when Viking and wotnot revealed Mars for what it is.
It strikes me that you're not really comparing like with like here. The canal thing, and what followed, was based around assumptions made to explain a specific observation. SETI isn't anything like that. SETI is about looking for something, it isn't about promoting a fanciful explanation for an existing observation.
Cliff wrote:I do not entirely agree wth you though that SETI is pure science. True as you say "if you do not look, you will never find". That is fair comment, to a point. But by the same token there are some people who ardently search for UFOs.
When you say "UFOs" here I assume you have in mind people who ardently search for evidence to back up the Extraterrestrial Hypothesis as an explanation for UFOs? Sorry, but that really isn't the "same token" at all. If you're going to make that sort of analogy then it works for any systematic search for evidence for or against a particular idea. In which case either any form of systematic search is akin to looking for evidence to back up the ETH or you've got to recognise that there's a difference between looking for reasonable evidence (and in the case of SETI an absence of evidence is as good a result as finding evidence) for a reasonable idea and looking for reasonable evidence for an unreasonable idea.
Cliff wrote:Again I could be eating my words. Over the years I have done a fair bit of observing, even before I became a "real serious" astronomer. I have seen some fantastic things but I have never seen anything that I would consider to be a convential UFO.
What do you consider to be a "convential UFO"? It would be a rare individual who spends many nights outside looking at the sky who hasn't seen an object in the sky that doesn't appear to be of natural origin and which they couldn't identify. That's the very definition of a UFO: an Unidentified Flying Object (please don't let the ETH followers convince you otherwise -- thankfully there are some in the ETH camp who do actually understand and acknowledge this).

In my years I've seen a good few UFOs. Thankfully, with a little bit of research after the event I've managed to turn the UFO into an IFO. I seriously doubt that I'm alone in this. I think the last time this happened to me was when I saw my first ever Iridium flare, not long after the launches started and before the phenonmenon had been reported in the popular astronomical press.
Cliff wrote:I am afraid as far as I am concerned SETI is almost in the UFO category.
I find astronomy fascinating enough in itself for me not to need UFOs or SETI.
Hmm, I'm not really sure what this is supposed to say. There are aspects of astronomy (and other sciences) that I don't find interestring and, yet, without those interests I still find astronomy fascinating. At no point do I feel the need to deprecate those things that I'm not interested in if I can see the point, purpose and scientific merit.

Now, sure, there are arguments against the scientific merit of SETI but, thankfully, the compelling ones don't have to stoop to likening the search for ETI with belief in the ETH explanation of UFOs.

Here's something to consider: when you go out at night with your eyes, bin's or 'scope you're going out to capture electomagnetic waves. Your reasons for doing so might be for pure entertainment, they might be for your desire to learn, they might be for pure science (any one of those reasons would seem to be a valid one). SETI is just a another method of studying electromagnatic waves and, having already found one "non-natural" source of such waves (the Earth), is checking the local area to see if there's another example of this astronomical phenonmenon.

So, if you're going to draw a parallel between (on the one hand) SETI and your use of your astronomical instruments and (on the other hand) belief in the ETH explanation of UFOs can you point me at the one example of alien visitation to a populated planet? Your time outside and SETI both come from seeing existing evidence; to make the analogy work then I'd expect to see the same thing for the ETH.
davep
Posts: 2814
Joined: Fri May 06, 2005 11:07 am
Location: South Lincolnshire
Contact:

Post by davep »

joe wrote:I'm sure the SETI people know exactly what they are doing and as I have not seriously looked at their website I may be talking out of some place other than my mouth but surely to goodness even if an exoplanet civilisation tried to contact us the chances or even the possibility of detecting a signal are vanishingly small.
Indeed they are.
joe wrote:How much power is needed to send a signal that will be picked up 10 light years away? That is assuming that we are fortunate enough to have a lifeform so close to us that thought of such a thing.
Well, of course, it would be highly fortunate but it does seem highly unlikely. No harm in checking though is there? As for the power thing, it's a few years now since I read up on this but I seem to recall the suggestion that an omnidirectional leak from a planet (based on the only example we've got to hand at the moment) is good for around 50 light years (there's a term for this -- a something sphere -- but I forget it now). For us that covers a good few systems but it's also a manageable number (I did have the number written down somewhere but I can't find it now, I'm sure it's a reasonably easy Google search to find it).

I don't doubt for a moment that even the most ardent (yet rational) SETI supporter will acknowledge the suggestion that nothing will be found and that it's like looking for a needle in a haystack (only, you don't know if the needle is even there, or in another haystack, or another you can't see, or...). It strikes me though that this search is one where a negative outcome is just as valid and as useful as a positive one.
joe wrote:What are the chances of two civilisations being able to broadcast and receive at the same minute fraction of the lifetime of their planets? This does not bring in also the hugely fortunate set of circumstances that allowed the evolution of intelligent life on this particular planet that we inhabit!
What are the chances? Very very remote -- but I think we all know that.

Besides, as any Douglas Adams fan will know, there actually isn't any life in the universe anyway.
Douglas Adams wrote:It is known that there are an infinite number of worlds, simply because there is an infinite amount of space for them to be in it. However, not every one of them is inhabited. Therefore, there must be a finite number of inhabited worlds. Any finite number divided by infinity is as near to nothing as makes no odds, so the average population of all the planets in the Universe can be said to be zero. From this it follows that the population of the whole Universe is also zero, and that any people you may meet from time to time are merely the products of a deranged imagination.
Cliff
Posts: 6600
Joined: Sat Dec 11, 2004 8:18 pm
Location: Manchester
Contact:

Post by Cliff »

Dear davep
I will have a go at a couple of your points (perhaps some of the others another time).
Basically I think the SETI thing is currently a complete waste of time. Possibly at some time in the future when our technology is more advanced, it might be worth looking.
Of course that is only my opinion, I could be eating my words next week someone might get a SETI result, but I doubt it? Indeed I would be very surprised.
Of course no one will never be able to prove that aliens do not exist somewhere else in the universe. SETI could go on forever and ever and even longer.
However, I would not entirely agree with you about several things. In particular, as things stand I think it is still an assumption that there is life elsewhere in the Universe (never mind supposed intelligent life that we will ever be able to communicate with). The life on Mars thing is still pretty tenuous, related to a few meteorites. OK there may be water on Mars, but that has been known about or certainly very strongly suspected for a considerable time.
According to several New Scientist mags I have read from time to time scientists still do not entirely agree as to exactly what constitutes life.
So if someone does pick up an alien signal there are still likely to be ongoing disputes about its authenticity.
There will be those who want to jump at believing it genuine, however tenuous the evidence might be, but others (like me perhaps) who would need a lot to be convinced.
We still only have very limited understanding about how Earth bound animals communicate eg it has recently been suggested that Navy sonar is damaging the poor old whales.
I think Joe said that he believes the SETI people probably know what they are doing. Well although I accept the SETI people are clever, I am not convinced they do know what they are doing. But as I said before hopefully some good spin off things might come out of SETI, but so what? Indeed, since I am inclined to suggest that SETI is a wild goose chase (at least at this time) then arguably I am suggesting they do not know what they are doing.
On the other hand I have misgivings about selling star names to the public - but people are making money out of it, quite a lot of money.
I am afraid that I am not a "Hitch-hikers Guide to the Galaxy" fan, so the Douglas Adams quote you made ..... is a bit meaningless to me.
If I recall correctly you sugested that the Martian Canal Furor revolved around just one observation. (I am sorry if I am mistaken about that).
The Martian Canal Furor went on for quite a few years and quite a few astronomers got dragged into it. I think part of the problem was that people wanted there to be life on Mars. By the way I think we also disagree about SETI as being a way of catching the general publics imagination. Although to be fair I do think that most people involved with SETI are genuine in their belifs even if I do not go along with them.
As far as i am concerned there are far too many fascinating things for me to do in astronomy than getting involved with SETI, which I think would be a waste of my time. If our lives get recycled and I come back, say for arguments sake, in several centuries time, perhaps (assuming humans have not become extinct or worse still destroyed the planet in the meantime) by then our technology will be advanced enough to make SETI worthwhile. At that stage I might be a bit more enthusiastic about doing it.
For now though as far as I am concerned it is still an assumption that Intelligent Extraterestrial Life exists, althoough of course I accept it probably does but as yet not certain.
Best wishes from the long winded grumpy Old Codger Cliff
stella
Posts: 1473
Joined: Fri Dec 03, 2004 2:41 pm
Location: 55° 57'N: 03° 08'W
Contact:

Martian canals

Post by stella »

"If I recall correctly you suggested that the Martian Canal Furore revolved around just one observation. (I am sorry if I am mistaken about that)."

Many observers reported seeing 'canals'. Schiaparelli started it all off in 1877,
but it was Lowell who suggested that they were artificial. They were also seen by Perrotin and Stanley Williams. Many other observers recorded them as soft shaded streaks, rather than the hard thin features proposed by supporters of the artificial intelligence theory.
Post Reply