1

Physiology & Medicine / Re: Does reasoning like humans exist in one species only ?

« on: Yesterday at 17:24:51 »

Humans became technological in less time that it took for isolated groups to become sexually incompatible, so say when the Europeans discovered a whole different race in South America, they could still mutually reproduce.

There's no reason that this is always the case. We had humans isolated enough that there were hobbits. OK, they died out, but had they not, they might have been a different species and they might have developed similar intellect. On other planets, there may be far more formidable barriers than our oceans, allowing one intelligent species to diverge, or allowing two such species to evolve separately without one killing the other. The latter seems kind of unlikely since the odds of both species coming into its intellect at the same time is incredibly small unless they figure out how to live a sustainable existence.

2

Plant Sciences, Zoology & Evolution / Re: Do Spiders Cooperate ?

« on: Yesterday at 17:17:03 »

There are communal spider species that band together in small communities to take down larger prey that would otherwise be out of reach of an individual.

The mathematics seems to be one of amount of supper per unit area. Each spider is capable of spinning only so much area of web as an individual, and twice the area means twice the prey captured.

Communal webs are larger, but still a lower area per capita, so they catch fewer victims per spider. But the larger webs allow the capture of larger prey that would be out of reach of an individual. So for small communities, cooperation yields more biomass per capita, but for even larger communities, this too drops off so you don't see massive spidey-hives like you do say with bees or something.

3

General Science / Re: Are Black Holes The Blackest Things Ever ?

« on: Yesterday at 13:18:46 »

what happens to the absorbed light ?

It gets warm, and to prevent it from getting warm enough to radiate IR light back out (ruining their nice high percentage), it needs to be pulled away by other means, presumably by something on the other side keeping it cool.

The Webb telescope needs to be kept cooled to just a couple degrees Kelvin, and most of that is done by completely blocking light from Earth and sun, but that only works so far, and active cooling (heat pumps) must be used to get it fully to where they need it.

So don't put a woolly tongue on the telescope.  Baaaa-d idea.

4

Physiology & Medicine / Re: Can JUST a head survive ?

« on: 27/05/2022 19:56:35 »

Could my head(or anybody else's head) remain alive and well if attached to the appropriate equipment

The technology may not be currently up to the task, but since your body constitutes 'appropriate equipment', the answer is very much yes. All it has to do is what the rest of you does.

You could always attach the head to a different host like the other end of the neighbor sheep producing a sort of 'push me pull ewe'.

5

Physics, Astronomy & Cosmology / Re: Does The Universe Spin ?

« on: 27/05/2022 15:32:53 »

Everything spins, but the universe isn't a thing. An object without a bounded size cannot meaningfully spin.

Ewe spin me right round quickly,
tight round, getting dizzy,
ralph a one pound ground round mound

Spin in relation to what?

Spin is absolute, and need not be in relation to any particular frame, although something's angular momentum is at least relative to an axis, but angular moment and spin (RPM say) are different things.

6

General Science / Re: Are Black Holes The Blackest Things Ever ?

« on: 27/05/2022 15:28:22 »

They're not perfectly black, but they're blacker than a place in space with no stars in it.

The black sheep don't quite win, but close.

7

Physics, Astronomy & Cosmology / Re: Can A Gravitational Wave Cause Physical Damage ?

« on: 27/05/2022 13:43:20 »

Can Gravitational waves Cause Physical Harm ?  say, they were mega strong ? What am I going to feel as they pass through me ?  Will I puke sheepy sick ?

It affects large things before small sheepish size things. At a moderate distance, Earth would definitely feel it, being stretched this way and that, causing earthquakes and volcanoes and such.  But if one was close enough to a source of such gravitational wave energy, the tidal forces of the masses involved would already be tearing Earth apart in a similar way via tidal forces, even in the complete absence of the thing putting out gravitational waves.

So point is, try to keep the sheepy pasture reasonably far away from really massive objects.

8

New Theories / Re: If there was one Big Bang event, why not multiple big bangs?

« on: 25/05/2022 21:30:53 »

Is an infinite universe easy, or hard to comprehend?

Most people have little trouble comprehending that part. It's not what's implausible. It's your physics that doesn't work. Matter suddenly banging into existence at some point in existing space, besides being a total violation of all conservation laws, also creates a gravitational singularity, even if it's only the mass of an apple, let alone a mass greater than that of the visible universe. There would be no light, new material, stars, atoms, or anything. It predicts a universe with zero light.
So I'm saying, push the idea on a non-science site, because it only works if a blind eye is turned to science.

So when I say in the title of this thread, "why not multiple big bangs?", it is not a reference to The Big Bang event, of which there is just one implied. It is a reference to possibly an infinite number of big bang type of events occurring all across space and over all time: an on-going and eternal/universal process.

Are you talking about spontaneous particles appearing like you get with pair production?  Nothing big like an apple? That would predict a steady state of greyness, with no receding objects, and everything sort of being born in a kind of heat-death state. Such a model was proposed a couple centuries back before entropy was understood and before expansion was observed.

Also, if new stuff gets periodically added for an infinite time, the universe necessarily must become full after some finite time. So is there a mechanism to remove old mass/energy?

However, from any local perspective, held by any past or present intelligent life form in the universe, infinity and eternity must be hard to fully comprehend.

Infinite time and eternity are very different things. Eternalism just says the universe isn't something that exists in time. It doesn't posit the boundaries of time or the lack of them.

9

Just Chat! / Re: a suitable pseudonym

« on: 22/05/2022 01:22:45 »

I had assumed it was HAL from the space odyssey books, but version c  - so not trying to kill everyone.

So much for not trying to leave an impression. It's short for Halcyon.

NOAX   would have been hard to work out.  No-one would have known it was Non-Oxide Adhesive eXperimental,  or a pop singer.   Best guess -    "No Axe to grind".

Last one was closer.
If you remember my answer to one of your other threads about who we are, I put out an answer about identifying biases (a post which was copied by a spammer bot). To do that, one has to hold a minimum set of base assumptions, so it means no axioms.
So I'm way beyond 'cogito ergo sum' since that statement seems to beg at least two such biases.

10

Just Chat! / Re: a suitable pseudonym

« on: 22/05/2022 00:13:46 »

Consider the abbreviations
People often tend to shorten names online, which I leant by experience.

That they do, which is why I pick a name short enough that it's not likely to happen. Besides, I often need to refer to myself in the 3rd person, and a long name just means a lot of typing.

However, your name is what you start with and why make people start with an impression that is miles away from where you are?

My name here is just a shortened word and not meant to leave an impression. I could have used 'Noax', which isn't meaningful on first impression, but that name does mean something, even if it isn't quite 'wearing your heart on your sleeve'.

11

Physiology & Medicine / Re: why is my skin so sensitive when I have a fever?

« on: 19/05/2022 16:14:22 »

Is this a known effect?

Very much so, especially for flu. It is similar to heightened sensitivity to sound and light, especially when feverish.

Is there a known (or likely) mechanism?
Is there anything I can do to limit it while recovering?

Apparently staying hydrated is a good way to limit it. Ibuprofen helps reduce inflamatory related symptoms, including the skin sensitivity. I found that acetaminophen does a nice job on headaches and fever, but not so helpful with the inflamation.

Benefit of covid: Our altered social practices have seemingly prevented about two years of all the common stuff I/we usually contract each year. Sorry this hasn't been entirely true for you.

12

New Theories / Re: If there was one Big Bang event, why not multiple big bangs?

« on: 17/05/2022 17:37:39 »

Mention a different alternative to "always existed".

This would require one to drop one or more naive bias.

"Always existed" is a phrase only meaningful to objects (a house, galaxy, the weather, etc.) contained by time. So if the universe is not reduced to an object contained by time, but is rather a structure that contains time, then it just exists. This is standard realism, a view held by Einstein and by probably the majority of physics that understand Einstein. If the universe is not a structure that contains time, then all of relativity theory is wrong, and there's not really an alternative thoery that has done its own generalization. So for instance, there's the neo-Lorentian interpretation, which says absurdly that all the equations that Einstein derived in relativity theory can be used to make any prediction, despite the fact that they're all based on premises that are wrong (such as the frame independent constant speed of light). But that's a view (used by nobody that actually has to work with physics) that posits the universe as an object contained by time, and thus is in need of being 'started'.

Dropping the bias of 'universe as an object in time' is not difficult, but if it is for you, then dropping the others will be out of reach, so I'll not go into other alternatives that require more out-of-the-box thinking. This is a science forum. Science is concerned with making empirical predictions, and none of the explanations of the existence of the universe make any empirical predictions, so they're not science.

It's like the question you asked about life elsewhere: If it's beyond the event horizon (which is currently just outside the Hubble radius and well inside the radius of the visible universe), then it cannot be measured by us and by any definition of existence that involves measurability, doesn't exist. That's a very different answer than the mathematical "any nonzero probability multiplied arbitrarily high results in a certainty".

13

New Theories / Re: If there was one Big Bang event, why not multiple big bangs?

« on: 14/05/2022 06:52:40 »

Would you mind posting a few words from your thoughts

For the most part, you seem to have gotten completely off track. None of your recent posts have been about multiple bangs or related theory. To be honest, I have little idea what you're currently proposing. You're just blogging random and mostly unrelated thoughts.

about how unique life is in the universe, given an infinity of time and space.

If life is of any probability greater than zero for any given star system, then given unlimited star systems, there must be life on an unlimited number of stars. Any other possibility is mathematically inconsistent.
This assumes infinite space (and thus infinite star systems), but not infinite time, since any given type of life is only good for a finite region of time: Too soon and there's too much violence and not time to develop stable life. Too late and entropy takes over and there's no energy left to support life. As it is, life has been on Earth about 4-5 billion years and all but the simplest life will be gone here in another billion. The planet will not support eukaryotic life soon, and that includes anything multicellular.

[Spoiler:]

14

Just Chat! / Re: A Short puzzle with dogs.

« on: 12/05/2022 15:01:04 »

Another physical solution:

Spoiler: show

Replace the river 'rod' with a mirror and shine a laser (a surveyors laser that leaves a line on the ground) from the dog to the reflection of the house

[Spoiler:]

15

Just Chat! / Re: A Short puzzle with dogs.

« on: 12/05/2022 14:52:34 »

I'm still working on the circle problem, but have had almost no time to do so. It's coming.

Maybe the dog can shorten the effort by jumping on a board floating on the river, saving steps. I presume such complications are not part of the problem.
This problem has a physical solution:

Spoiler: show

Just put pegs in a board where the house and dog are, and a rod representing the river. Tie a string to the dog and the house looped around the rod and pull it tight. It will move to the shortest path, which momentarily touches the river 4/7th of the way, or ~43 m west of the house.

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New Theories / Re: If there was one Big Bang event, why not multiple big bangs?

« on: 18/04/2022 20:11:54 »

Many of us recognize the graphic of the birth of the universe, with the pinpoint beginning from a single "primordial atom" (per Georges Lamaitre), that is expanding outward into any imaginable future we want to entertain.

While I've seen may graphics, I can find none that were authored by Lemaitre himself. He certainly didn't posit the universe beginning from a small state. The visible universe perhaps, but that never grew to infinite size in any finite time. So I think you're misrepresenting the general big bang concept.
I don't see how a graphic can depict an infinite thing and a finite thing in the same picture.

The graphic depicting the universe growing from a single primordial atom to an infinite expanding universe doesn't seem to be right to me, but it seems to be the current consensus.

That's a common naive misconception. It is certainly not any kind of consensus. You said you don't want to learn any actual physics, so I can not really help you. Your blog is already 800 posts and still asking the most basic questions.

I prefer an "always existing" universe, where Big Bangs naturally occur; they occur in any patch of space containing enough matter and energy to allow gravity to form a Big Crunch/Bang

Well that's the problem with this model. Any collection of matter/energy (let alone what we see in our visible universe) squeezed into a small existing space like that would constitute a black hole (and a violation of energy conservation), and it would be in a crunched state before it could ever bang. It couldn't happen once, let alone multiple times.  The Milne model works something like that, but only because it is a zero energy solution, so no black holes form.

I think you agree that the universe is infinite. Correct me if not.

I think this question was directed to me, despite lack of mention of me in the post.
The size of the universe is unknown, and also coordinate system dependent and also dependent on the direction the measurement is taken. So for instance, in the approximate inertial frame of Earth, the universe is physically bounded and under 28 BLY across. The visible universe is often quoted as being larger than that, so the often quoted figure doesn't use inertial coordinates for the measurement.

17

New Theories / Re: If there was one Big Bang event, why not multiple big bangs?

« on: 17/04/2022 18:16:17 »

We are talking "Bogie Logic" here, lol.

Yea, I noticed.

Go in a straight line into space forever and tell me when you run into the wall, crash wham!!!

First of all, spatially, you can go in a straight line forever and not even reach stuff that you can see in front of you, regardless of speed. That part is known.That's hardly any kind of evidence of the universe being spatially infinite or not.
Secondly, finite space does not imply it has an edge. Space on the surface of Earth is finite, yet there's nowhere where you can go in a straight line and wham into the end of it. So much for "Bogie Logic".

Thirdly, you can draw a straight line in the temporal direction and you will very much 'bang into a wall'. There may or may not be meaningful 'universe' on the other side of that wall, but the wall is very much there, which seems to be how you define a boundary according to your logic.

Just a brief example:
Let's assume that you are a jet eng. designer.
You had been asked to design a jet engine for an airplane.
However, you have no clue about the size and the total requested load of this airplane.
Can you do it successfully?
Don't you agree that a get engine for 100Kg should be different from a jet for 1,000,000,000 Tons?
Maybe for that kind of load a jet engine is not good enough.
So how could it be that we have any sort of theory for a universe without any knowledge about its total size?

Example is inapplicable unless you can name one engineering project (or any empirical observation for that matter) that depends on whether or not the universe has finite spatial extent or not.

[Spoiler:]

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Just Chat! / Re: A Short puzzle with dogs.

« on: 15/04/2022 14:34:32 »

To get this straight, the nasty dog is restricted to the circular path and always moves at 4x your speed in the direction that takes it closer to the point on the circle to which you are nearest.

Seems pretty simple.

Spoiler: show

Run away from the dog. As it picks a direction, you change course and follow a circular path as well. This works fine as long as you're within a quarter of the distance from the center to the edge. So you are capable of keeping the dog at max distance until this point.  Starting at that point, you break for the edge, and angle your path in a 1-4 ratio from the dog's motion, just to buy a little more space.

Is this enough?  Circle of radius 1 and the dog needs to travel 3.14.  I am at 0.25 and need to travel 0.75.  No problem. I don't even need to do the angle bit.

I think a curved path might be optimal and it would seem an interesting problem to determine the max speed that the dog could run before you could not escape the circle. I suspect it's over 5x, but didn't work it out.

19

Just Chat! / Re: There's a section with "similar topics" appearing.

« on: 13/04/2022 18:24:36 »

It's been there forever, and it seems to be a simple best-match on what it sees as keywords.

    The Similar topics suggested included:
a)   "Can I Use Washing Up Liquid To Wash Hands And Hand Soap To Wash Plates?"
b)   "How long must a prism-shaped corridor be to render a light-source invisible?"

The first one obviously matched 'plates', but no clue why it thought b) should be on the list.

20

Just Chat! / Re: A Short puzzle with dogs.

« on: 12/04/2022 19:23:44 »

The calculus appears pretty complicated, but the picture shows some trivial facts.
First, to answer a prior question, I assume everything is a point, the problem otherwise not really being fully defined.

You've approximately shown nearly half the distance traveled. At the actual point (har!) the distances between them have been halved, the answer is simply twice the distance already traveled.

The remaining distance is a square still, but rotated something like 30 degrees or so. Each time the distance is halved, the square gets rotated by that amount, so the dogs are going to circle each other an infinite number of times before the collision after a total path length.

My attempt: The problem can be broke into tiny pieces, so let's say a dog moves a trivial distance x, almost a straight line. It will curve just a little bit, but for sufficiently small x, a straight line, bringing it exactly x closer to the next dog. This leaves the same initial condition, but rotated and a little closer. Therefore the path length of each dog is exactly 1 by symmetry since each movement of x reduces the distance between them by x.