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I bet you didn't know that this thread would have a part 2

IamMetaldave

BaZmO* wrote: »

This post is the 10,000th post

Pipped.

Mod: Continuation from the old thread, which is here.

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lan

dasdog wrote: »

I was inferring UDP

dasdog wrote:

but the data would need to be transferred with error correction [...] and over secure tunnels [...] which would greatly slow the process down

Why would you use UDP if you need error correction?

dasdog wrote: »

and I'd love to know how securing a tunnel has no overhead.

I didn't say to use a tunnel, you did. I suggested just encrypting it. Yes, there's some additional processing overhead, but the bandwidth will still be the limiting factor.

You could include also include a hash in the encrypted data every 100MB or so to ensure it wasn't tampered with.

Realt Dearg Sec

Ah I seem to have accidentally clicked into the "I bet you didn't understand this" thread.

Fourier

Fourier wrote:

I'll just finish off (probably back March-ish)

So I wanted to close this off, but left it a month late! With the black hole seems like now would be a good time.

The last two things I haven't spoken about with Quantum Theory is the idea of the observer and the whole issue with "okay what the hell is actually going on"? Especially since I made what can seem to be an odd claim at the end of the last post:

Fourier wrote:

Unfortunately we just don't know what are the sensible concepts/descriptions for the fundamental stuff and there are strong reasons (in the form of mathematical theorems) to think we basically can't understand them.

In this post I'll deal with the observer and how it relates to the fundamental weirdness of Quantum theory. The next and last post I'll have on Quantum Theory is the "what the hell is going on" part.

So, the observer. This has caused a pile of crazy pseudo-science, but funnily enough I often see "skeptics" on the net over-egg it and say Quantum Theory doesn't have observers. This is false. It does have observers but it's for mundane reasons.

Quantum Theory involves probabilities and probabilities are basically about betting and knowledge, this is why there is an "observer".

So say a weather service on a Tuesday gives a 38% chance of Thursday being sunny. Then they see the way the weather patterns are on Wednesday and they update that to a 67% chance of Thursday being sunny. Why? Well it's because on Wednesday they've observed a few new facts that make a sunny Thursday more likely. They've learned something. They have observed something and updated how they'd bet based on this new knowledge.

However note how this is subjective and depends on the observer. Somebody operating another weather station sleeps in on Wednesday and doesn't make detailed observations. They won't be able to update their probabilities the same way. Say they only catch the details of the weather in the evening rather than tracking it all of Wednesday and that's only enough information to raise the chance of a sunny Thursday to 45%.

That's what's going on in quantum theory. You do an experiment, get a result and then update your probabilities/bets for the next experiment based on that. This does involve the "observer" and it is subjective but for the same reason the weather does.

So if Quantum Theory is just about betting on microscopic experiments what's the problem? Or what's the difference between it and betting on the weather? It's a very weird difference, but one that comes up when surveying people's preferences.

Imagine you try to survey people in Ireland on their favourite Indian political party and include brief descriptions of each political party on the survey. If you look at the statistics after they break certain mathematical rules statistics and probabilities are supposed to obey. Betting on the weather, dice rolls, horse races, etc obey these rules but surveys don't. Why would this survey break the rules? Because people in Ireland typically know nothing about Indian parties. Your descriptions probably created their opinions. You weren't measuring an opinion that was already there. Until your survey they had no opinion on the Bharatiya Janata Party.

So the big difference is that your attempt to record the result in fact creates the result. That's what Quantum Theory is about. Statistics and betting when your attempt to learn creates the results. Quantum Mathematics shows up in opinion surveys. The statistics of microscopic systems behave like opinion surveys.

The problem is this: Okay John from Blanchardtown thought nothing of the Bharatiya Janata Party until I gave the survey. However that an atom had no Energy until I checked is a bit odd. Not that it had zero energy, that's still a value of Energy, literally the concept didn't apply. Just like John wasn't neutral on the Bharatiya Janata Party, he had absolutely no opinion.

Same for position. A particle isn't anywhere until you check. In fact because whether something shows up as a particle or a wave or a field depends on what device you use, the stuff isn't even a particle until you check.

This is the craziness that bothered Einstein, not randomness like several books claim. National Geographic had a great video on this (see Einstein's main problem at 0:43)

https://www.youtube.com/watch?v=9mXJK86GCsI

Now what Bohr thought ties back to John from Blanchardstown. Yes John doesn't think anything about the Bharatiya Janata Party, but he still exists and has several other properties besides opinions about Indian political parties. Similarly the stuff down there doesn't have Energy, Momentum, Position, etc until we or other large objects force them to. However that doesn't mean they don't have other properties we don't know about.

However Bohr made the bold claim we'll never know anything about those properties. Why he said that or more so why as of 2019 it looks like he was right leads into the final post about what the hell is going on...

EDIT: Just for veracity's sake here is an example of a paper that uses the mathematics of quantum theory to explain a political survey:
https://arxiv.org/abs/1604.08270
The point isn't the specifics just the last line where they say that they needed the mathematics of quantum theory to explain surveys on Bill Clinton and Al Gore, as well as another on Baseball players Pete Rose and Shoeless Joe Jackson. No microscopic systems involved, but there was clear evidence the survey itself was partially creating the opinions and that's why you needed quantum theory

Capt'n Midnight

The second successful launch of SpaceX Falcon Heavy means that the $17Bn that NASA has spent on SLS has been spaffed up a wall.

If SLS becomes a successful launcher it will still be 10 times as expensive as SpaceX per launch, so a billion dollars a go. Up in smoke. Literally.

SLS uses flight proven tech from the Space Shuttle ( even reusing leftover engines) , or in the case of the upper stage stuff an engine was first tested in the 1950's. - Reinventing the wheel is expensive :rolleyes:

Boeing are the main contractor for SLS.

They are also part of ULA that has had a monopoly on military space launches for the last decade, Atlas and Delta have had a 50 year track record in US spaceflight, apart from the bits bought from the Russians, including engines that were sitting in a warehouse for ages.
( though SpaceX are starting to slowly eat into this market )

[/RANT]

The irony is that despite Boing getting money for old rope the EU and US are shaping up for a tariff war over subsidies to Airbus and Boeing.

Morbert

What's especially counterintuitive about QM is how fundamentally observer-dependent its descriptions appear to be.

E.g. Fourier talked about how an observer's use of the concept of energy when describing an atom is contingent on observation.

However that an atom had no Energy until I checked is a bit odd. Not that it had zero energy, that's still a value of Energy, literally the concept didn't apply.

We might be tempted to conclude some objective point like "the energy of the atom is brought into existence when it is directly measured".

Instead, this restraint on describing the atom in terms of a definite energy is specific to the observer. A 2nd, distant observer may speak of the energy of the atom without ever measuring it if they, for example, measure the energy of a 2nd atom appropriately correlated with it.

To strain Fourier's analogy to breaking point: Surveyor A, located in Ireland, will not be able to speak of Irish attitudes towards Indian parties prior to surveying them. But if it is the case that Irish attitudes will match Scottish attitudes, then surveyor B, located in Scotland, would be able to speak of Irish attitudes towards Indian parties by surveying only Scottish people. The suitability of the notion of "Irish attitudes towards political parties" is surveyor-dependent.

[edit] - An interesting article discussing QM's subjective character

https://www.technologyreview.com/s/613092/a-quantum-experiment-suggests-theres-no-such-thing-as-objective-reality/

There are quantum foundations research projects which attempt to recover "observer-independence" in QM. How successful they are is up for debate.

mikhail

Capt'n Midnight wrote: »

Never underestimate the bandwidth of a station wagon full of tapes hurtling down the highway.
- Andrew S. Tanenbaum

https://what-if.xkcd.com/31/

Fourier

Fourier wrote: »

However Bohr made the bold claim we'll never know anything about those properties. Why he said that or more so why as of 2019 it looks like he was right leads into the final post about what the hell is going on...

So now, what's actually going on? I'm not going to concentrate on why Bohr thought this, but more so why we now think he is correct.

So fine, we know particles don't really have Energy (or position, momentum, etc) unless we or other large objects check to see their Energy. Our checking seems to actually create the value.

However whatever properties they do have surely once we know those properties we can make a scientific theory of them?

I won't go into the details, but there are a set of theorems that constrain explanations of Quantum Mechanics. The most famous of these theorems are the Kochen-Specker, Bell and PBR theorems. It doesn't matter what each of them say, it's a bit technical, but the end result is that they leave only a few ways to explain Quantum Mechanics.

According to these theorems the only possible explanations for what's happening underneath QM are:

The different parts of the world communicate with each other no matter how far apart they are. So the material in your body is "talking" to the material near the M58 black hole whose picture was revealed last week. In addition to this every little bit of material in your body stores an infinite amount of information.
The future communicates with the past. They both determine each other. So sometimes a particle might go off course because it hit a wave sent back in time from its future self.
There are multiple parallel worlds.
Quantum Mechanics isn't correct, it just looks like it is.
The properties of the underlying stuff has no mathematical explanation. It can't be modelled or understood enough to be described in a predictive way.

I know the list is pretty crazy, but these are the only options. Everything else has been ruled out. However all these options don't have equal standing.

The first one is in explicit contradiction with Relativity and despite billions of tests this instant communication has never been seen. It has been proven that theories like this have to be very carefully fine tuned to avoid contradicting our observations.

Similar problems apply to the second one. None of these influences from the future have been seen and again they'd need to be pretty carefully tuned.

The the third one has a similar major problem matching experiment. Quantum Mechanics gives pretty precise probabilities for experiments. Like "There's a 78.6% chance the Geiger counter will click in the next minute". The Many Worlds approach has a real problem with getting these precise numbers out. Despite sixty two years of work every attempt to do so has failed.

The fourth one might seem like a good one, however there has been a theorem proven (Colbeck-Renner theorem) that basically shows even if QM is wrong the theory that replaces it will suffer the same problems with "what the hell is going on?". Plus no experiments suggest Quantum Mechanics is wrong.

So that leaves the last option. The opinion of those who originally created Quantum Mechanics, e.g. Bohr, Heisenberg, Pauli.

So Quantum Mechanics is basically a theory for betting on and managing your knowledge about the Energy, Positions, Momenta and other physical properties of subatomic systems even basic ones like being a particle or a wave. It's a bit different from the normal rules of betting because none of these properties are natural to subatomic systems, we and other large objects create them/cause subatomic systems to develop them when we check for them. Unfortunately their real/natural properties are not susceptible to mathematical comprehension or description and thus may remain outside of scientific understanding. The End.

BaZmO*

Hummingbirds can’t walk

Chancer3001

BaZmO* wrote: »

Hummingbirds can’t walk

After fouriers post above, the simplicity of that actually made me lol.

Ariadne

Chancer3001 wrote: »

After fouriers post above, the simplicity of that actually made me lol.

I prefer those kind of ''I bet you didn't know'' posts because Fourier's posts make me feel like an inferior human :pac:

ytpe2r5bxkn0c1

"Dreamt" is the only English word that ends with the letters 'MT'.

I think

Chancer3001

Nevaeh Shaggy Destroyer wrote: »

"Dreamt" is the only English word that ends with the letters 'MT'.

I think

Theres also daydreamt. Undreamt. Redreamt.

ytpe2r5bxkn0c1

Chancer3001 wrote: »

Theres also daydreamt. Undreamt. Redreamt.

Same base though.

Wibbs

Succubus_ wrote: »

I prefer those kind of ''I bet you didn't know'' posts because Fourier's posts make me feel like an inferior human :pac:

The best bet is to take a leaf from the quantum world; that is one's intelligence can only be ascribed a value if it is observed and even then it can only be pinned down in one specific way, therefore like the building blocks of reality, it's best to keep the buggers guessing by saying nothing.

BaZmO*

Chancer3001 wrote: »

BaZmO* wrote: »

Hummingbirds can’t walk

After fouriers post above, the simplicity of that actually made me lol.

Yeah I thought that the contrast might be a bit stark alright.

KathleenGrant

Nevaeh Shaggy Destroyer wrote: »

"Dreamt" is the only English word that ends with the letters 'MT'.

I think

What about I amn't?

cdeb

That's NT, not MT!

(Or even n't)

Dick phelan

An estimated 35 million people in China live in caves, more than the population of Australia

CHINA’S RAILWAY LINES ARE SO EXTENSIVE AND LONG THAT THEY COULD LOOP AROUND EARTH TWICE

There are 37 cities in China bigger than Chicago

FrancieBrady

partyguinness wrote: »

The guy in the white suit next to Lee Harvey Oswald when he was shot is still alive. He also survived Pearl Harbour.

https://en.wikipedia.org/wiki/Jim_Leavelle

DJ legend John Peel also had an amazing connection to this story:

http://liberalengland.blogspot.com/2016/09/john-peel-and-lee-harvey-oswald-in.html

"It's a story that I've told so often that you get to the point where you don't really believe it yourself, it just seems so unlikely.
"But then in one of the bits of film of that press conference, we were all standing in this room and they had the identification parade in the basement of this building and they said - Henry Wade said - that this is the man that's been charged in the assassination of President Kennedy, and they brought in Lee Harvey Oswald. And he stood there looking slightly puzzled and alarmed for a while, and then was taken away again.
"In one of the films of this, which they showed on British television, they showed that Jack Ruby was in the room as well - which I didn't know he was until I saw this film they sort-of panned across the room and in the last few frames you can see me and my friend Bob standing there looking like tourists."

KathleenGrant

cdeb wrote: »

That's NT, not MT!

(Or even n't)

Oops!

Kat1170

Wibbs wrote:

The best bet is to take a leaf from the quantum world; that is one's intelligence can only be ascribed a value if it is observed and even then it can only be pinned down in one specific way, therefore like the building blocks of reality, it's best to keep the buggers guessing by saying nothing.

Better to remain silent andÂ be thought a fool than to speak and to remove all doubt.Â
As it were

New Home

Jadayupara, the largest avian sculpture in the world

New Home

And still on the topic of the black hole...

Fourier

In the Ancient Egyptian religion anal sex prevented the recieving partner from performing magic on the giver. This even works between Gods and mortals. The Coffin texts (2130–1938 BC) has the soul of a normal man claim he is immune to the power of the god of creation Atum's magics. In his own words:

"Atum has no power over me, because I copulated between his buttocks"

Coffin Text 258d

4068ac1elhodqr

Dick phelan wrote: »

An estimated 35 million people in China live in caves, more than the population of Australia

CHINA’S RAILWAY LINES ARE SO EXTENSIVE AND LONG THAT THEY COULD LOOP AROUND EARTH TWICE

There are 37 cities in China bigger than Chicago

In some small mining towns in Aus practially everyone lives below the ground, it's so darn hot (Coober Pedy).

China outbuilt the US in terms of 200+meter skyscrapers by a ratio of about 7:1 (x13 higher for sub 200m).

In 2018 they built more skyscrapers (x88) than any other country, for the 23rd year in a row.

By 2060 their GDP will be about the same as the EU & US (combined), India won't be far behind.

Franz Von Peppercorn

Fourier wrote: »

So Quantum Mechanics is basically a theory for betting on and managing your knowledge about the Energy, Positions, Momenta and other physical properties of subatomic systems even basic ones like being a particle or a wave. It's a bit different from the normal rules of betting because none of these properties are natural to subatomic systems, we and other large objects create them/cause subatomic systems to develop them when we check for them. Unfortunately their real/natural properties are not susceptible to mathematical comprehension or description and thus may remain outside of scientific understanding. The End.

So back to that cat in the box that time.

Did he survive?

New Home

They'll have to check, give them a chance. :pac:

mzungu

Arctic and Antarctic trace their names to the meanings of "bears" and "opposite of bears."

Father Hernandez

A very interesting story

https://en.wikipedia.org/wiki/300_million_yen_robbery

BaZmO*

That reminds me of the classic Fake Security Guard scam. A crook who garbs himself as a security guard, places a sign reading “NIGHT DEPOSITORY OUT OF ORDER — Please leave deposits with guard” in front of a bank’s night depository, and stands off to the side with a large cart, into which he places the money and receipts handed to him by trusting customers. The crook then makes off into the night with the deposits, keeping the cash and tossing the receipts.

Frank Abagnale (of Catch Me If You Can fame) is believed to have pulled off this scam.

In Tigard, Oregon, in August 2008:

"Two men made off with hundreds of dollars in cash by dressing as security guards, standing outside a bank’s night deposit slot and persuading people to hand over their money because the slot was broken.
The men offered to make the deposits for customers at the Washington Square branch of Wells Fargo Bank the next day when the bank reopened, said Jim Wolf, a Tigard Police Department spokesman.

“Wells Fargo had absolutely no idea who these men were,” Wolf said.

He said the men wore uniforms and had badges and guns. The night deposit slot was covered by a blue engraved sign saying it was out of order.

The men offered to collect the deposits by putting them in a black box they had, Wolf said. The deposits came from businesses that normally use the slot to deposit the day’s receipts from their tills.

Two people who gave deposits to the men said the sign over the slot read “Out of Service.”