stromgo (u/stromgo) - Readit News

stromgo commented on Warp drive's best hope dies, as antimatter falls down bigthink.com/starts-with-... · Posted by u/WithinReason

mnw21cam · 2 years ago

You're making a very interesting distinction between the experimental result, which is that antimatter follows the same space-time curve as normal matter, and the dashed hope of warp drives, which is that antimatter causes the same space-time curve as normal matter.

However, if antimatter were to create a negative curvature but follow positive curvature, then you would be able to put a lump of normal matter next to a lump of antimatter, connect the two together, and the whole mechanism would spontaneously accelerate forever, breaking the laws of conservation of energy and momentum. For that reason, I think this experiment also gives us high confidence that antimatter causes exactly the same space-time curvature as normal matter, even though we haven't gathered enough antimatter to see it creating a normal space-time curvature. In essence, gravity is symmetrical.

stromgo · 2 years ago

Maybe it helps to consider all 4 possibilities for the sign of the gravitational mass of antimatter, and the sign of the inertial mass of antimatter?

(-,-): antimatter would fall down, but we could break conservation laws with a mechanism.

(+,-): antimatter would fall up, but we could break conservation laws with a mechanism using electrically charged particles.

(-,+): antimatter would fall up, but ruled out by the experiment.

So what remains is (+,+)?

stromgo commented on Does time really flow? New clues from intuitionist math quantamagazine.org/does-t... · Posted by u/nikolasavic

andrewon · 6 years ago

But a digital computer at present in this world may not be a good reference to the capability of the computer that supposedly simulate this world. We know nothing about the "real" world that computer resided, and nothing about that computer.

stromgo · 6 years ago

We do know that the real world is richer than the simulated world, since it holds a computer that runs the simulated world. Therefore if you exist, then it's more likely that you're the result of evolution in the real world than the result of evolution in the simulated world.

Imagine the warehouse-size computer that is needed to simulate a bacterium here on Earth. Computers are dusty, and dust contains bacteria, so if you're a bacterium, then it's more likely that you're one of the billions of bacteria in the dust on the computer, than the bacterium being simulated by the computer. The same reasoning should hold for other worlds.

stromgo commented on Saturn's largest moon may be the only place beyond Earth where humans could live blogs.scientificamerican.... · Posted by u/mastry

mannykannot · 6 years ago

Am I missing something here?

"On the surface, vast quantities of hydrocarbons in solid and liquid form lie ready to be used for energy. Although the atmosphere lacks oxygen, water ice just below the surface could be used to provide oxygen for breathing and to combust hydrocarbons as fuel." [my emphasis.]

They are proposing splitting water to get oxygen for burning hydrocarbons to produce energy - but splitting water itself takes a lot of energy, and low-entropy energy at that. Could this process possibly result in a net increase in useful energy?

stromgo · 6 years ago

I'll answer the energetic question. Splitting water produces oxygen and hydrogen, so with our oxygen we have the choice between burning hydrogen or burning Titan's hydrocarbons. Burning the hydrogen would bring us back to square one, so the question is whether burning hydrocarbons yields more energy than burning hydrogen. It appears to not be the case. Some numbers I found online:

  burning 1 mole of O2 with hydrogen yields 572 kJ
  burning 1 mole of O2 with methane yields 444 kJ
  burning 1 mole of O2 with butane yields 443 kJ
  burning 1 mole of O2 with octane yields 437 kJ
  burning 1 mole of O2 with glucose yields 467 kJ

https://personal.utdallas.edu/~metin/Merit/MyNotes/energySci...

https://www.ausetute.com.au/fuelenergy.html

stromgo commented on The unending quest to explain consciousness bookforum.com/print/2604/... · Posted by u/hoffmannesque

normalnorm · 6 years ago

I have no problem with agreeing that computation can emerge from neurons. For example, one can show how different neural configurations correspond to logic gates, persistent memory (this requires recurrence) and so on. This is precisely what I mean by valid emergentist models. No magic steps, just complexity.

The problem is that you start by stating that "consciousness is a computation", but I don't know if this is true, and neither do you.

> Is the problem that you don't believe that consciousness can emerge from elementary computation, or you believe that it is possible but we have no proof of it?

My problem is that your hypothesis that "consciousness is a computation" is not testable, and so it does not count as a scientific theory (according to the standard Popperian falsifiability criterion).

Unless/until we have a scientific instrument that measures consciousness, we are just assuming things. I assume that other humans are conscious (by analogy), but I don't know it to be true in a scientific sense.

So it's not a matter of what I believe or not, it's a matter of what science can investigate or not. So far, it looks like the phenomenon of consciousness is beyond its grasp.

stromgo · 6 years ago

When you said

> With consciousness, the emergentists are not capable of pointing at the first principle, or building block.

...it sounded like there were no plausible candidates. If computation is a candidate, then it's certainly something they can point at (with the caveat that it's only a candidate and not currently testable). I think if instead you had written something along those lines and avoided the words "not capable of", then hoseja and I wouldn't have reacted.

stromgo commented on The unending quest to explain consciousness bookforum.com/print/2604/... · Posted by u/hoffmannesque

normalnorm · 6 years ago

You can point to a protein being expressed by DNA, and then understand how many protein molecules amount to cells, then tissues, then organs. There is a first principle guiding you all the way, even though the complexity is staggering.

There is no such first principle with interactions of neurons, in the sense that we know of no quality or property of a neuron that could amount to the phenomena "consciousness", in the same way that individual transactions amount to a stock market.

Without this first principle, it's just magical thinking disguised in scientific language.

stromgo · 6 years ago

Consciousness is a computation, and neurons are certainly capable of elementary computation.

So the building block has been pointed at (neurons), and its property given (computation). Is the problem that you don't believe that consciousness can emerge from elementary computation, or you believe that it is possible but we have no proof of it?

stromgo commented on WebAssembly developer.mozilla.org/en-... · Posted by u/August-Garcia

igouy · 7 years ago

That paper does not report "WebAssembly is running at 67% of native speed in Firefox and 53% of native speed in Chrome".

That paper reports — "… applications compiled to WebAssembly run slower by an average of 50% (Firefox) to 89% (Chrome), with peak slowdowns of 2.6× (Firefox) and 3.14× Chrome)."

When you write "53% of native speed" that's really confusing!

stromgo · 7 years ago

Sorry, I reformulated the findings for easy consumption. Why is it confusing and not an improvement? Ask 10 people what speed is 89% slower than 100 mph. See how many give the article's intended answer (53 mph).

stromgo commented on WebAssembly developer.mozilla.org/en-... · Posted by u/August-Garcia

Waterluvian · 7 years ago

So this mentions that wasm can have near native speeds and work alongside JS for performance reasons.

Is this currently true or is this more about what the future hopefully looks like?

I recall reading that wasm is an in-progress thing and really isn't that fast in comparison yet.

stromgo · 7 years ago

The paper Mind the Gap: Analyzing the Performance of WebAssembly vs. Native Code reports that, on average, WebAssembly is running at 67% of native speed in Firefox and 53% of native speed in Chrome (called 50% slower and 89% slower in the paper). Whether 67% can be called "near" 100% or not is subjective.

stromgo commented on 23andMe Informed Me My Husband and I Are Related thecut.com/2018/12/23andm... · Posted by u/duman

spacehome · 7 years ago

You share (about) 1/128 of your genes with a third cousin. The chance of any (particular) recessive trait being passed on from both parents as a result of the inbreeding is a whopping 1 in 65,536.

stromgo · 7 years ago

I'm not sure what you computed. The interesting question is to pick a recessive trait from one of the parents and ask for the chance of it being passed on. The probability that it's being passed on from the parent who has it is 1/2. The probability that it's being passed on from the other parent is (1/2)*(1/128). The combined probability is 1/512, not 1/65,536.

stromgo commented on Philosophy Has Made Plenty of Progress blogs.scientificamerican.... · Posted by u/chablent

eli_gottlieb · 7 years ago

>Faith in science is not an unreasonable assumption—says me who holds that assumption—but it's faith nonetheless.

Faith is when one acts on a belief without having any rational reason for it. My rational reason for believing in science is simply: it works!

stromgo · 7 years ago

Indeed. Subway cars move forward without any horse pulling them, how is this miracle possible? What turned out to work was the steam engine, and now electromagnetism, explained by science. What didn't turn out to work was an elite team of people praying for the train to move.

stromgo commented on Planets evenly spaced on log scale johndcook.com/blog/2018/0... · Posted by u/tacon

dr_zoidberg · 8 years ago

The asteroid belt doesn't have nearly enough mass to be/have been a planet[0]. Largest thing there is Ceres, followed by Vesta, of which only the first qualifies as a dwarf planet.

There was an hypothesis about it being the remnants of a destroyed planet[1], but that was mostly an idea to support the Titius-Bode law[2], which was disproved a few hundred years ago.

[0] Currently about 3x Ceres mass, though it may have about Earth mass early in its history. See https://en.wikipedia.org/wiki/Asteroid_belt#Formation and https://en.wikipedia.org/wiki/Asteroid_belt#Evolution

[1] https://en.wikipedia.org/wiki/Phaeton_(hypothetical_planet)#...

[2] https://en.wikipedia.org/wiki/Titius%E2%80%93Bode_law

stromgo · 8 years ago

The qualifier "dwarf" doesn't mean that the celestial body is too small to be considered a planet, it means that it hasn't cleared the neighborhood around its orbit. (Blame the IAU if you find this counterintuitive). This means that your conclusion is wrong: the asteroid belt actually has enough mass to be a planet.