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speakeron

436 karma · joined July 12, 2014

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speakeron··on A tiny Swiss company thinks it can help stop climate change
> Not allowed by thermodynamics. Otherwise you could create free energy by continuously burning and recapturing the same carbon.

That doesn't have to be the case; the carbon you capture may not be in a burnable form. E.g. if carbon dioxide were captured, additional energy would be required to split off the oxygen before the carbon could be 'burned' again.

speakeron··on Strangeness of Black Holes
The particle goes through the event horizon in finite time according to its own clock (and will then hit the singularity in finite term however it tries to travel).

Think of the view of it by an external observer as being 'frozen' at the event horizon as kind of optical illusion caused by the extreme warping of spacetime. For a non-evaporating black hole (as described by general relativity), the 'last' photon coming off it will indeed be at infinity (or with infinite redshift). If (when) the black hole evaporates, the external observer will see that and of course there will be no more photons from the infalling particle.

These two different views are hard to reconcile from our human perspective of how the world works, but they really do come from the mathematics of general relativity.

Here's a really excellent and short video which attempts to explain this in ten minutes. (His explanation of how a Penrose diagram works is fleshed-out in more detail in the Susskind lectures I mentioned above).

PBS Spacetime - What happens at the Event Horizon

https://www.youtube.com/watch?v=mht-1c4wc0Q

speakeron··on Strangeness of Black Holes
> How do these two things mix? A particle experiences asymptotic time dilation when it crosses the event horizon and the rest of the universe ends in that moment. Then the black hole evaporates and lo and behold the universe is not ended.

I don't know if that's necessarily correct. From the point of view of an object falling through the event horizon, nothing special happens and they can look outwards normally; whereas an observer some distance from the black hole (and maintaining that distance) sees the falling object fall slower and slower and becoming more redshifted. The falling object also become shorter in the direction of travel (according to the external observer) and end up 'smeared' on the horizon.

Leonard Susskind shows this using a Penrose diagram in lecture 5 or 6 (I think, but they're all worth watching) of the Stanford Topics in String Theory lectures[1]

[1] https://www.youtube.com/watch?v=NZ-ElsvYKyo

speakeron··on Strangeness of Black Holes
I would also recommend (8 lectures)

Leonard Susskind Topics in String Theory

https://www.youtube.com/watch?v=NZ-ElsvYKyo

Despite the name this is largely about general relativity and black holes and other horizons. The best detailed description of black holes for laymen (assuming you have algebra and basic calculus) I've ever seen.

speakeron··on Who Really Built the First Electric Rock ‘n’ Roll Guitar?
> The original color of the >1954 Fender Stratocaster was a three-toned sunburst.

Two-tone, surely.

The two-color sunburst finish became a three-color sunburst finish in the first half of 1958 with the addition of an “in between” red hue.[1]

[1] https://www.fender.com/articles/gear/the-history-of-the-fend...

speakeron··on Why is cognitive function impaired at high altitude?
But what the article doesn't address is that the same effect is seen in flying at high altitudes without supplementary oxygen, even in the absence of sleep deprivation, dehydration, and simple physical exhaustion.
speakeron··on Consumption of a dark roast coffee blend reduces DNA damage in humans
While I'm always happy to hear good news about coffee (although as an espresso aficionado, I'd be hard pressed to consume half a litre a day), given the obvious difference between coffee and water, I don't see how this can be a 'single-blind' study.
speakeron··on We can confirm that there was a successful 51% attack on Ethereum Classic
> These statements directly contradict each other.

They don't contradict each other at all.

> Once block 26 comes online, block 6 is a permanent feature of the blockchain.

What defines the 'blockchain'? It's the chain with the most work. Outside of a centralized checkpointing mechanism, the only definition of the valid blockchain is the one with the most work behind it.

speakeron··on Should I Flush It? Most Often, the Answer Is No
One solution is the bidet shower[1][2] that's common in Islamic and Asian countries. Nothing to clog up the sewage system and a rather civilised way to keep clean.

[1] https://en.wikipedia.org/wiki/Bidet_shower

[2] https://www.twogreenbackpacks.com/2014/01/17/how-to-use-a-bu...

speakeron··on Vitamin D, the Sunshine Supplement, Has Shadowy Money Behind It
I'd go further and say you that, if you're on medication, you shouldn't take any supplements without first checking with your doctor.

With regards to vitamin K, all the versions of the supplement I've seen have a specific warning on the bottle that they're not to be used if you're also taking anticoagulants.

speakeron··on Vitamin D, the Sunshine Supplement, Has Shadowy Money Behind It
> I will thus cut down on supplementation to avoid vascular calcification.

Current good practice is to also supplement with vitamin K when taking D. This is to promote carboxylation of osteocalcin, so calcium is directed into bones rather than soft tissues[1].

[1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5613455/

speakeron··on The Art of Not Dying: the First Emperor’s Pursuit of Immortality
> You woke up from the abyss this morning.

Actually I woke up directly (and, apparently, seamlessly) from a dream. (I went lucid a little too carelessly surged to a waking in the same manner as you come up from the bottom of a swimming pool).

To be fair, though, I did wake up into the dream from the abyss. But since the abyss is timelessness, how would we know the difference?

speakeron··on String.hashCode() is plenty unique
However perfect it is, it can only guarantee no collisions if the size of the strings you're hashing is equal or lower than the hash size.

In this house, we obey the pigeonhole principle.

speakeron··on Before 1905, there were no ‘hormones’
"It was the ability to, for the very first time, measure hormones down to the billionth of a gram. That’s like if you took a gram of salt and threw it into the ocean, and it had a powerful impact."

That's about 10 orders of magnitude out. Not as bad as the vacuum energy calculation, but still quite a wide miss.

speakeron··on Hello quantum world
The short answer is that statements like "spooky action at a distance" are an attempt to shoehorn quantum mechanics into a classical framework. It doesn't have any meaning in that sense.

The long answer is here:

https://www.youtube.com/watch?v=0Eeuqh9QfNI

speakeron··on BYTE Magazine
> My favourite project was the video camera he made from a 64kb DRAM chip

My first job in computing was as a bench repair engineer for shop-returned Sinclair Spectrums. (Pretty busy time since they had a huge failure rate mainly due to an under-specified transistor in the DC-DC converter).

Since we had plenty of components available, I had a go at doing this by lifting the lid of a ceramic 4164 (might have been a 4116) with a soldering iron and hacking together a bit of stripboard to plug into the expansion bus of a Spectrum.

It worked a treat with a few frames per second refresh rate. (I had to remap the non-sequential ram lines in software to get a sensible image.)

speakeron··on The Time Everyone “Corrected” the World’s Smartest Woman (2015)
That's how I got to understand it when I first heard about the problem in the early 90s. (Of course, I also wrote a simulation.)

The problem itself can be rephrased in an even simpler manner where Monty doesn't open any doors at all. Once you've picked a door, he then gives you the option of either staying with that door or changing to both of the other doors (where you get to keep the best prize behind them). Given that formulation, almost everybody would switch.

speakeron··on Melatonin: Much More Than You Wanted to Know
> I think an important thing to consider is that if your going to take large amounts of vitamin D, you should also be getting enough magnesium to prevent unhealthy calcification.

You should be taking vitamin K as well.

speakeron··on The Defeat of Reason
> but isn't (except in the Everett version)

Not even in the Everett version. When we make a measurement to discover the large-scale patterns, we have to invoke the Born Rule and see just one outcome of the quantum wave. The other worlds of the Everett Interpretation are simply 'magical'.

speakeron··on GDPR: Programmatic ad buying plummets in Europe
Nothing stops a site showing ads; they just have to think of creative ways to target them. It's a new opportunity, as all changes of environments are.
speakeron··on GDPR for lazy people: Block all European users with Cloudflare Workers
Tu quoque is not a logical fallacy. There's no logical step that's violated. It's an informal fallacy.
speakeron··on What happens when I choose to “Suppress Ads” on Salon?
> The giant pile of dirt on my back yard is proof that I did hours of hard work with a tea spoon.

It isn't proof: you could have used a digger. The point of Bitcoin-style proof-of-work is that everyone has to use a teaspoon, and if you want to 'go back in time' and rewrite transactions you have to do more work with a teaspoon than everyone else is doing.

speakeron··on Bitcoin Miners Fried in Game of Chicken
That's true in the general case, but it only happens after a difficulty drop. Until then, miners dropping out will raise the block time (again, just a tiny bit). For cryptocoins with more dynamic difficulty adjustment, this process happens a lot more quickly.
speakeron··on Detecting Consciousness (2017) [pdf]
> Advanced meditators are able to be vividly conscious in dep sleep.

How can that be known except through self-reporting? At least with lucid dreaming, experiments have shown communication from the subject via eye signals[1]. Has a similar thing being done with meditators?

[1] http://www.historydisclosure.com/scientific-experiment-prove...

speakeron··on Spectre/Meltdown Pits Transparency Against Liability
> What uses cases involve running new untrusted code on legacy unsupported systems?

Well yes, you shouldn't be doing that (particularly the 'unsupported' bit). The thinking here, I suppose, is that Meltdown makes privilege escalation straightforward once a malicious party has access to the system via another vector.

In my company, we run self-hosted physical servers (i.e. we're the only user on the systems) and debated whether to disable the page table isolation fix since we were seeing about a 30% performance hit.

The decision we took was that we would accept the performance hit since Meltdown means that any unauthorized entry into the system has a privilege escalation path since kernel memory is essentially readable by any process. (Quite an easy and quick decision, really.)

speakeron··on New porn laws will mean Pornhub asks for your name and address
Well, that's a 'stimulating' site. It seems to be channeling the 1980s UK paper the Sunday Sport[1] (famous for its "World War 2 Bomber Found on the Moon" headline).

My favourite line so far is: "He has been banned from every farm in Britain". I can't imagine what it looks like without an ad blocker.

[1] https://en.wikipedia.org/wiki/Sunday_Sport

speakeron··on Graham's Number Is Too Big to Tell How Big It Is
Sounds a bit like Yudkowsky's number[1] (your main step is the first one, everything else is salad), which is a computable version of Rayo's number[2])

[1] http://googology.wikia.com/wiki/Yudkowsky%27s_Number

[2] https://en.wikipedia.org/wiki/Rayo%27s_number

speakeron··on Graham's Number Is Too Big to Tell How Big It Is
Well, you could plug Graham's number into the Bekenstein–Hawking formula[1]. The formula defines the area and there's a factor of the plank length in there, but Graham's number is so overwhelming that the the result is pretty much Graham's number in any units you want.

[1] https://en.wikipedia.org/wiki/Black-hole_thermodynamics

speakeron··on Graham's Number Is Too Big to Tell How Big It Is
> David Metzler's series "Ridiculously Huge Numbers"[1] is a good introduction to this. It goes rather well beyond puny little integers like Graham's number.

Yes, David Metzler's series is great and, I would say, essential viewing if your interest in large numbers is piqued.

While he doesn't go through some of the big numbers talked about her (TREE(3), SCG(13), etc), he gives an excellent explanation of the fast-growing hierarchy. This is really the closest thing we have to a 'standardized' way of comparing the sizes of very large numbers.

I would also recommend Giroux Studios' 'Extremely Large Numbers'[1], which takes a similar style to Metzler's videos and goes further with the fast-growing hierarchy. (Does something called 'infinite collapsing functions' sound interesting...?)

[1] https://www.youtube.com/watch?v=vq2BxAJZ4Tc&list=PLUZ0A4xAf7...

speakeron··on Graham's Number Is Too Big to Tell How Big It Is
> But it's the m(x) that's actually large in that example.

Sure, it's large (mindblowingly so), although I'm not quite clear exactly how you define m(x).

It's hard to get a grasp on just how much vastly larger each of these 'rockstar' numbers is to the previous one when you ascend this conceptual hierachy. (To a certain extent, that's the point of the article.)

You could make a K(K(K(...(n)...) function where you painted a K on each particle in the visible universe (about 10^80) and it still wouldn't come close to Loader's number. The point is that you can't simply recurse TREE and hope to get a number that's conceptually any bigger than TREE itself.

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