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@MishaVanMollusq @RickiTarr
Once you learn about the Penrose number you kinda stop believing that it's real at all. It's absolutely insane.

@samhainnight @MennoWolff @Basmitharts @MishaVanMollusq @RickiTarr Roger’s just this guy…

@MennoWolff @MishaVanMollusq @RickiTarr
Definitely, but TL-DR it's essentially is the measurement of how ordered the universe had to be at the beginning to evolve into what we see today.
Comes out to a 1 in 10 to the power of 10^123 chance.

@Basmitharts @MishaVanMollusq @RickiTarr
Hmm. That's not a lot

@Basmitharts @MennoWolff @MishaVanMollusq @RickiTarr
Huge odds, but if you don't have time yet, surely you can crack off 10^10^123 universes before breakfast. If there's a way to make universes (which there obviously is) but time doesn't exist yet, just keep banging them out until one works.

@MennoWolff @Basmitharts @MishaVanMollusq @RickiTarr I thought this might have been a play on the original meaning of "google".

@Basmitharts @MishaVanMollusq @RickiTarr How real is any number, when you really get down to it? (My god, it's full of puns! Sorry, distracted myself from my point for a moment there. Ahem...)

Our entire number system is really just a model with properties that make it conveniently reusable in a lot of different contexts. The really outlandish numbers like this are exactly the sort of thing we should expect when we let a power user play around with it.

Reality is vast and profound, and our system for describing it can be a little inadequate sometimes. But it's not the number that's outlandish. The real outlandishness is in the universe we are trying to describe with it.

@RickiTarr Most of bloody quantum theory, for a start!

@RickiTarr Heat pumps can heat your home by taking heat from outdoors even when it's colder outside than in your home.

@tezoatlipoca @auscandoc @statsguy @RickiTarr
It's basically a refrigeration cycle. Cool vapor enters the compressor, which compresses it, heating it in the process. The hot, high-pressure vapor flows through the long, zig-zagging condenser tubes. The vapor heats the tubes, which radiate the heat into the surrounding air. That's why the back of your fridge is always warm. As the vapor releases its heat, it cools and condenses.

Then the cooled fluid, still at high pressure, is forced through a throttle. It's usually a more complex valve, but the principle is the same. As the fluid passes through a narrow orifice, its speed increases, causing its pressure to drop. (Bernoulli principle) The drop in pressure causes it to cool almost instantly and partially vaporize.

The cold, low-pressure fluid/vapor mix then enters the evaporator, another set of zig-zagging tubes. Being very cool, the fluid absorbs heat from the metal tubes, which absorb heat from the inside of the fridge, cooling it. As the fluid warms, much of the remaining liquid evaporates.

From there, the warmer vapor enters the compressor, which starts the cycle again.

Now imagine that the inside of the fridge is actually the inside of your house, and the outside of the fridge is the air outside your window. The refrigerator is now an air conditioner.

Now imagine installing your air conditioner backwards. The hot condenser coils are inside your house and the fan is blowing the air off the cool evaporator coils outside. That's a very simple example of a heat pump.

Think about the air conditioner again. Even when your house is nice and cool, and it's really hot outside, the unit is still able to move heat from inside your house to outside. It's just like your fridge. Even though it's much cooler inside the fridge, the refrigeration circuit is still able to increase the temperature difference.

That's how a heat pump can do it in reverse.

To be really efficient, a heat pump doesn't use the outside air. The most efficient heat pump I've ever seen is the chiller unit in the Vancouver Convention Center, which is on the downtown waterfront. Long pipes extend out into the harbor, which is always pretty close to 5°C. Pumping the water through a huge refrigeration circuit cools the convention center in summer, and by running the circuit in the other direction, heats it in winter. The engineer who runs it told my engineering class that they can turn a 5°C difference between incoming and outgoing water into a 30°C difference between inside and outside temperature.

A residential heat pump works the same way--when it's installed properly. I've heard horror stories of homemade heat pumps that turn the house into a cold, damp nightmare!

@violet @tezoatlipoca @auscandoc @statsguy @RickiTarr thanks for that explanation. This is the easiest to understand explanation I've seen so far

@violet @tezoatlipoca @auscandoc @statsguy @RickiTarr best explanation for a heat-pump I’ve seen. I work with them on a daily basis, still like to think of myself as a wizard

@auscandoc @statsguy @RickiTarr

I had an aeronautics lecturer who said he would go and watch the jumbo jets taking off at Leeds/Bradford airport, and he still couldn't "believe how they got off the bloody ground".

@auscandoc @statsguy @RickiTarr
Heat pumps were one of the things in thermodynamics P-chem where my brain went “nope, you better memorize because this shit doesn’t fit in the mental model”. It was rough. Every time people talk about heat pumps now, my brain gives a tiny side-eye.

My brain also noped relativity in Physics. Luckily the professor didn’t test for that one.

@statsguy @RickiTarr

I wanna mansplain this so bad

@statsguy That is really strange!

@statsguy @RickiTarr Heat pumps made a lot more sense to me when someone said it’s like the coils on a refrigerator, but the refrigerator is inside out.

@statsguy @RickiTarr
They are basically a fridge with the door open to the outside world.

@RickiTarr There's a species of jellyfish that is "biologically immortal”.. in the absence of predation or disease, they can basically regenerate forever.

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

@FlagrantError @RickiTarr there's also a human cancer that's been alive and growing since the 1950s that's immortal.

https://en.m.wikipedia.org/wiki/Henrietta_Lacks

@RickiTarr that bread makes you fat.

@RickiTarr That you won't get a fatal electric shock as long as there is no ground contact.