What is the Universe expanding into..

Do you think there was anything before the big bang?

  • I don't think there was anything before the Big Bang

    Votes: 56 12.5%

  • I think something existed before the Big Bang

    Votes: 200 44.7%

  • I don't think the big bang happened

    Votes: 54 12.1%

  • I think the universe is part of a mutiverse

    Votes: 201 45.0%
  • Total voters
    447
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Galu

Galu

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Joined 2018
It's a long time since I was in London's Science Museum, Steve. My father took me there when I was a little boy and I returned on my own in my teenage years.

How it must have changed since then!

To see Spitfires and the like up here, we can visit the National Museum of Flight in East Lothian.

A fairly recent acquisition is the Concorde.
 

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system7

system7

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Joined 2008
Some good planes there. Is the one on the right a Lightning? No, I don't think so. Do I also spot the German Jet that turned up too late to save the Fuehrer's bacon? My favourite antique aeroplane is the Vulcan Bomber. It just looked the business! Had a terrific last Hurrah in frightening the Argentinians half to death in the Falkland Isles.

The old Spitfire engineers I worked with told me tales of filing down rivets on Spitfires to make them go 10 knots faster. And rebuilding engines in 3 hours after the pilot had pressed the supercharge booster "Tit" button to get a Messerschmitt off his tail. Wrecked the engine apparently, but in a crisis you needed it badly.

I wouldn't have minded a trip in Concorde.

We used to see it every evening in London around 5PM setting off for America.

Child of its time, I suppose.

Here's a lovely place in France. Falaise. Scene of one of the grimmest battles of WW2. But now an exquisite quiet small town:

Falaise "Ma Normandie" - Chateau Guillaume Le Conquerant - YouTube

The Castle belonged to William the Conqueror who was no peasant. Richest man in Europe by my estimation. The French do town planning very well. The central square is full of nice outdoor Cafes which get warm even in February.
 
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Galu

Galu

Member
Joined 2018
system7 said:
Some good planes there. Is the one on the right a Lightning? No, I don't think so. Do I also spot the German Jet that turned up too late to save the Fuehrer's bacon? My favourite antique aeroplane is the Vulcan Bomber. It just looked the business!
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The one on the right is the Soviet Union's MiG-15. and the other's an Me 163 Komet by the looks of it.

There's a Vulcan at the National Museum of Flight. Guess who's got an Airfix kit of it in his stash! :)
 

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system7

system7

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Joined 2008
mchambin said:
Thanks, this is good stuff.
I was mostly interested in the data encoding to resist high bit errors.
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It's a deep subject. Information theory - Wikipedia

But a few rules apply.

A channel has a maximum error-free information carrying ability based loosely on the product of bandwidth and signal to noise ratio.

The most power efficient way to send data is with a high entropy signal on a low entropy carrier. This means the carrier resembles white noise until you decode it.

By coding most efficiently, you reduce power requirement to get the signal through.

Sputnik, in 1957, and the subsequent development of the space program, generated a great deal of interest in reliable communication in the presence of noise. It was suddenly a very real problem, and it was no longer possibly to glibly say ‘just use more power.’ As a result, a great deal of work was done in channel coding.

“What really changed the whole picture was space communication. Because power is very expensive in space - the generation of power, the weight of the power supply. And that’s when the industry, and the research in general began to think much more seriously about communication in the presence of noise. Space changed the picture entirely...”[Interview with Fano, R. 2001]
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There were actually a number of factors that made channel coding so perfectly suited to the problem of deep space communication.

Foremost, as mentioned, power is very expensive in space.

The deep space channel – the channel for communication with space probes –almost perfectly matches the theoretical noisy channel model that Shannon presented in his original paper, which was very well understood.

Bandwidth, which is used up by coding, is relatively plentiful in space.

As we mentioned, equipment complexity made coding such an expensive propositionthat most people wouldn’t seriously consider it. But for an ultra-expensive space mission, the percentage cost of the coding equipment is small. In addition, each dB saved by coding resulted in more than a $1000,000 of saving in the communication equipment. And that’s a $1,000,000 in 1960.
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http://web.mit.edu/6.933/www/Fall2001/Shannon2.pdf

Which means that it is the encoding where the most improvement has been made, And hence reduced power requirement.
 
system7

system7

Member
Joined 2008
Puns about "Lighter" aside, I thought that was the most jargon-filled baffling article I have ever read! I have learned what an "Attowatt" is, but do I care. :D

Almost as exciting as the 14.55 at Doncaster on 24 Oct is this intriguing announcement that NASA will reveal something exciting about the Moon on Monday:

NASA has teased “an exciting new discovery” about the moon.

The space agency will unveil the news at a major event, and while details of the discovery remain under wraps for now, NASA has said that the discovery “contributes to Nasa’s efforts to learn about the Moon in support of deep space exploration”.
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Nasa moon announcement: when the space agency will reveal its ‘exciting new discovery’ - and latest rumours | The Scotsman

My Odds:

10-1 On: Ice Cubes at South Pole.
5-1: Moon is made of Green Cheese after all.
500-1: Little Green Men are selling old spacecraft for scrap.

Can't Wait! :)
 
Galu

Galu

Member
Joined 2018
The breaking news is that the NASA probe risks losing its Bennu sample.

Images show that a small piece of rock has wedged the door of the sample container open and, as a result, some of the sample is escaping.

The probe is believed to have originally collected some 400g of asteroid rock and dust.

Osiris-Rex: Nasa probe risks losing asteroid sample after door jams - BBC News

EDIT: A sampling image sequence is shown in the above link - very clear images!
 
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system7

system7

Member
Joined 2008
Galu, you do know, don't you, that excessive interest in Sci-Fi is considered unhealthy?

Fan of Sci-Fi? Psychologists Have You in Their Sights

This supposes that the real world of unemployment and debt is too disappointing for a generation of entitled narcissists. They consequently migrate to a land of make-believe where they can live out their grandiose fantasies.
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Something to do with "Entitled Narcissm". But what is wrong with THAT? :D
 
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