h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

Wonderful!

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Is that actually true? I ask because the microwave background peaks at 160GHz according to a quick Google, which is about a hundred times the UHF band that an analogue TV can tune to. I'd also seriously doubt that the background radiation would detectable amongst the noise generated by the sun, man-made stuff and of course the TV set itself, otherwise we presumably wouldn't have needed radio telescopes to discover it in the first place.

Arnie (or anybody who knows the answer),
I'm enjoying delving into all this waves and quantum stuff but I'm just a bit thrown by references to the 2nd Law of Thermodynamics and entropy.
What I can't understand is that it says on Wiki that the bigger the system the more entropy there is. Well, if that's the case how come there are billions of stars and galaxies being born in the gas clouds of the star nurseries? That can't be entropy, can it?

try A467714

Key thing with entropy is to remember that many explanations and theoretical uses of entropy use a *closed* system. The universe is probably a closed system. The earth is not a closed system. Stellar gas clouds and stellar nurseries are not closed systems.

What this means is that entropy can decrease in an open system due to input from outside. However, of necessity that input from outside increases the entropy where it came from.

Put simple in a closed system entropy increases. But not necessarily uniformly. So whilst the overall effect is an increase, within localised areas within the system it is entirely possible for entropy to decrease. Otherwise we wouldn't be here.

This area of confusion is common and leads to the 'evolution violates the 2nd law of thermodynamics' argument - which is tosh.

p.s. I don;t think Wiki does say that - not on my reading. Could you highlight here the section that you were reading which gave rise to this?

Ictoan,
I enetered 'entropy' and came to the page where there's a picture of a drink containg ince. There I clicked on 'second law of thermodynamics' written in blue and then came to the page with the info. I'm trying to unravel.

ok, will try that. Have a look at the H2G2 page though and see if that helps, and even if it doesn't read it anyway as H2G2 is better than Wiki any day

Dave: or anyone! Anyone got the frequency range of an analogue TV tuner? I trying to discover whether it actually crosses the cosmic radiation frequency range.

Hmm. Well. A bit more searching seems to reveal that cosmic background radiation extends over quite a large range which does include the MHz range that analogue tellies work in.

I've possibly misunderstood the initial graphs (Fig 22.1) in http://pdg.lbl.gov/2002/microwaverpp.pdf though.

"it says on Wiki that the bigger the system the more entropy there is"

I've been reading the pages you mentioned and it doesn't, to me, say that. Can you quote which bits lead you to that conclusion and we may be able to straighten it out?

Entropy, in some ways, represents the total number of molecular configurations that the system can be in (that have the same energy). By increasing the number of atoms/molecules in the system, you generally increase the number possibilities/arrangements of the molecules/atoms - leading to an increase in entropy.

Well, the static on your tv would be background radiation plus a whole lot of other things. So it wouldn´t work too well for trying to detect it.

Ictoan, you're right, there is a very slight overlap:

http://www.blake-uk.com/serv_trade_industry_info_analchannels.aspx

this link is quite safe despite the page name . Still think the levels would be far too low though - the automatic gain control in the telly would adjust to display the strongest signals it could find.

nice one!

I guess that's where the '1%' figure comes in. I.e. it is there but only minimally.

I haven't read anything from the Dalai Lama, but I've read & heard many comments about similarities between QM, GR and eastern mystical traditions, especially Buddhism. It seems to me that many fields in modern science are having to address the problem of limitations on what information is even theoretically possible to find out. QM has Heisenberg's Uncertainty formula that tells us how accurately we can possibly measure something at very small scales. GR's speed limit on light determines whether an observer in one point in space and time can possibly know about anything at all at other points in space and time.

However, it is a VERY big leap in logic from demonstrating that *SOME* things are unknowable or uncertain to the buddhist principal that *ALL* things are unknowable or uncertain, i.e. "All is illusion".

So, Lucky, I think there is some small interesting connection to be made between QM and mysticism, but I don't think it's really as significant as it appears at first glance. Yes, QM & GR have made firm conclusions about physical reality that are anti-intuitive and contrary to our daily experience. But the main reason for that is that QM describes things that happen on very tiny scales and GR describes things on very large scales, both of which are totally outside the scale of our every day life experiences.

But I totally agree with you on one thing. I think the "spooky" and "mysterious" images in which QM & GR portray physical reality are very cool and worth meditating and reflecting upon. If we had a clear cut, logical model that predicted "everything" to extreme precision then there would be no more mystery and no more need for science. Science is all about seeking to understand the mysteries we experience in the physical world. That's why I think science is so cool and also what I see as the main connection between science and mysticism.

What I find most interesting about Buddhism is its very keen insights into human psychology and perceptions of the world around us. If you really want to explore the connections between science and mysticism then I recommend delving more deeply into neuroscience. That is an investigation into the one portal we humans have to perceive reality. And I think you'll find plenty of "spooky" and "mysterious" anti-intuitive conclusions that the field has been uncovering.

It sounds like the Dalai Lama's book is about a mystic's investigation into modern science. I highly recommend a book by a science journalist who describes many scientists' investigations into mysticism - "Rational Mysticism" by John Horgan. I thought it was a very cool book and I learned a lot about science and mysticism at the same time.

I'm glad that an obviously intelligent person who does not have a background in science is still interested in science and I encourage you to find out more. I think this h2g2 forum is a pretty good place to get a better sense of the science without having to study all the details for many years. How many of us have the luxury of being a full-time student for more than a few years? (Although I think I did pretty well in that department. I managed to spend 14 years in universities plus several more years interspersed in intern-type jobs exploring various fields. And the biggest accomplishment was somehow avoiding a doctorate. I still haven't really figured out what I want to be when I grow up.)

>>"If we had a clear cut, logical model that predicted "everything" to extreme precision then there would be no more mystery and no more need for science."

If we had a perfect deterministic model, we'd still face the practical inability to measure all of reality accurately enough, and end up with predictions of the future dissolving into chaos.

Malken42,
I agree. I think it's great to look into the small and the big in the universe. I spent much of my youth cycling around in the country lanes near the that great mysterious white dish pointing into the sky - the Jodrell Bank Radio Telescope - and wondered what those radio signals from outer space were all about.
at
The young Dalai Lama sitting at night a window of one of the 1,000 rooms of his Himalayan Palace gazed through his brass telescope and wondered about similar things. Following his exile he spent many years travelling the world and speaking with people like Zeilinger, Popper, Bohm, von Weizäcker.

For myself, I would have probably chosen a career in astronomy had the dice fallen differently. However,I was destined for other work.
Now that I have retired I have the time to pursue as a pastime my earlier interests.

The Dalai Lama's book is introduced with a quotation from an ancient Buddhist scripture, The Great Flower Ornament:
"In each atom of the realms of the universe,
There exist vast oceans of world systems."

"In each atom of the realms of the universe,
There exist vast oceans of world systems."

If by "atom" he means literally an atom, then this statement is wrong. There are in fact a finite number of fundamental, separable particles present within an atom...

Well, as I remember atom is a greek word actually meaning indivisible. So I do wonder about the translation, what the original word used actually means.

Arnie, you must obviously see that this is a translation from an ancient Tibetan text and that the meaning is not in the words used but in the sense.

Are you being obtuse or pedantic?

It is a valid point. That is what I think is a lot of the problem here, people using words from science when describing certain mystical things, which then make it seem that they are the same thing.