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Physics, Astronomy & Cosmology / Re: Does math ability vary with culture?

« on: 02/12/2021 09:35:06 »

It is a simple understanding. But after years of learning differences and similarities of school programs (Western and Russian mostly) and of the factors about being ‘technical’ or ‘humanitarian’ thinking to be distinguished in a high school I came to accept the next.
The subject here is for very young brains, right? In some brains, mathematics is built in the same way as knowledge of the native language. Up to senior school those who get the mathematics easily, are successful in physics and chemistry and even biology by translating other subjects to equations, diagrams etcetera. This is more about logic, might be. And some pupils who are brilliant in languages might be troubled in mathematics if they don't put much effort into it.
Regarding the school programs, they are pretty much the same, as I mentioned for Western and Russian knowledge. Might be a difference in load intensity, but the result after senior school is the same.
I would agree that culture or traditions are not  playing any vital role in absorbing mathematics. This opinion I could get from history and what I know from having Eastern acquaintance now.
There are a lot of differences, but when it comes to mathematics, everybody is on the same page.

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Physics, Astronomy & Cosmology / Re: Who is monitoring global space junk?

« on: 01/12/2021 16:44:40 »

Anyone that gets hit by it.

Exactly (except the largest pieces that pose a considerable threat, reported globally).
'Global' - are those which reached the Earth atmosphere and surface, might be correct.

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Physics, Astronomy & Cosmology / Re: Can we ever truly describe space as empty?

« on: 20/10/2021 09:00:05 »

Maybe as we learn more about the universe we will need new words to describe new relationships and phenomena. But for now, we don't need to quibble about which word we will use to describe "everything"

I think, we need new words and terms for many notions and concepts, some of them waiting 100 years ('time', 'space', nothingness' and so forth).
Oxford and Webster dictionaries do the job, searching new words around the world, and if a word is new and used and understood in the same way and mostly in many countries (in English), they put it as a candidate to be added to the dictionary.
Scientific definitions look as waiting something new to happen (as we might expect always).
Until then questioning of the terms and definitions are travelling throughout minds and discussions.

4

General Science / Re: Statistical analysis to assess forecast

« on: 18/10/2021 15:22:47 »

Comparing the forecasts should be done for each forecast separately to itself, giving an error to each one.
The acceptable error should be stated.
ANOVA uses independent random samples, which might not fit, as the forecast uses training data, not random.

1. Values verification (multidimensional as mentioned by @evan_au might be done by RMSE (Mean Squared Error) for each predicted value.
2. Dichotomous (yes/no) forecasts.
3. 'In machine learning applications where logistic regression is used for binary classification, the MLE minimises the Cross entropy loss function.’ - Wikipedia.

Combining forecasts using a formula looks not possible, assuming the forecasts were done with different models.
Model improvement can be done, running the prediction for already known values, and checking the variance.

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Physics, Astronomy & Cosmology / Re: What is TIME?

« on: 09/10/2021 09:27:23 »

Isaac Newton presented a point in space and time separately. Meeting someone needs: address (3 - dimensional coordinates) and time - the fourth dimension.
After 200 years Albert Einstein merged spacetime as a 3-dimensional model. Without time as a 4th dimension.
And after 20 years more we’ve got the concept of ‘arrow of time’ by Arthur Eddington.

Arrow of time depending on the stuff in the universe, the microscopic matter and the configurations. Entropy started to grow and will continue to grow for the future.
Arrow of time gives us an impression that time passes, flows, and we progress through different moments.
Past is not more real than the future, the past is that we know more about (any book, memory, fossil, that we can look at) that we believe gives us reliable knowledge of the past. There are no history books written about the future.
We have different access to the past and the future.

A movement in time as in space would presuppose the possibility of moving backwards in time and remaining still in it.
But you cannot remain absolutely still in time (only in relation to some reference systems), and you cannot go back in time (until proven otherwise).

There is no ‘earlier’, ‘now’ and ‘later’. Clock is just doing the same thing over and over again. We might have lived in a universe with the existence of things that are doing the same thing over and over again in a predictable way, which is not taken for granted. Clocks are something that can measure a passage of time. And there are many clocks in the universe, showing different time to a distant observer.

There should not be a confusion of terms and concepts, while going through theories.

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Physics, Astronomy & Cosmology / Re: Can we ever truly describe space as empty?

« on: 07/10/2021 10:29:25 »

For about 2500 years since Democritus till 2012, when the Higgs boson, discovered at the CERN, there might have been a question about emptiness between particles.
Today - definitely 'no'. The field is there.
If all the objects around us are constructed with particles and fields, the field might be called an object.

Object (noun)
1. A material thing that can be seen and touched.
2. A person or thing to which a specified action or feeling is directed.

A physical object or physical body (or simply an object or body) is a collection of matter within a defined contiguous boundary in three-dimensional space.

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Technology / Re: Is there a specific sound frequency that discourages birds?

« on: 07/10/2021 08:10:49 »

During this discussion, you could try to tame birds.
But be aware of animal rights activists.

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Physics, Astronomy & Cosmology / Re: Is the sequence of physical events continuous or discrete?

« on: 05/10/2021 08:51:07 »

To add all of the above.

Today physics doesn't tell us that time is discrete. Maybe in the future quantum mechanics will tell us about quants of time. Time and space quantization will give both of them in a discrete packets.

Time has rules of what comes one after the other.
The laws of physics start from a moment (a state of a system at one instance of time), then tell what happens next, using the patterns, using the physics (laws) to tell what happens to the next subsequent moment.

One good embracing example would be The Nyquist–Shannon sampling theorem [...] ‘which serves as a fundamental bridge between continuous-time signals and discrete-time signals. It establishes a sufficient condition for a sample rate that permits a discrete sequence of samples to capture all the information from a continuous-time signal of finite bandwidth.’

The sampling theorem introduces the concept of a sample rate that is sufficient for perfect fidelity [...] that no actual information is lost in the sampling process. (Wikipedia)

The theorem used a lot of works and notion given by Whittaker, Borel, Kotel'nikov.

In simpler words, we consider time as continuous in a certain system with pre-conditions, using small enough quanta of time to sample a physical quantity, so that it can be reconstructed without loss of information.

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Physics, Astronomy & Cosmology / Re: Astronomy VS astrology

« on: 30/09/2021 09:08:09 »

Reminds me of Timothy Leary or someone trying to sell you a hippy ethos.

It is always possible to dive into Jung and history, to get rid of the sense (in this case).

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Physics, Astronomy & Cosmology / Re: Astronomy VS astrology

« on: 29/09/2021 11:38:48 »

Thanks Tommy J. I find Jordan Peterson very interesting and have watched many of his presentations this one is very informative reveling more than I have considerd befor.

Thank you.
I am glad that it came to the point that right. Likewise I am quite a fan of him

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Physics, Astronomy & Cosmology / Re: Astronomy VS astrology

« on: 29/09/2021 09:15:18 »

‘Astrology has not demonstrated its effectiveness in controlled studies and has no scientific validity,  and is thus regarded as pseudoscience.’ - Wikipedia

But at the same time, for ancients, it was first of all the way of finding regularities, and the way of going beyond the observance and exact knowledge.
 
I like this scientific explanation:

Nowadays, probably, this is a manipulation with known regularities, patterns, an algorithm, which one may jungle in front of the public and show ‘predicted’ things to become true, make people believe in them.

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Physics, Astronomy & Cosmology / Re: Does gravitational time dilation/GTD really cause gravity?

« on: 24/09/2021 10:21:02 »

Everything above helped from all of the participants (Not for me only, I believe).

How much do you simplify at an early age, how much do some teachers really understand their subject?

I have no experience of my own that is enough to compare the oversimplification between generations in physics. But for other key disciplines I would confirm, it is there.

Which is enough to suggest that any quantum field theory for gravity would be unlike anything else you've seen.

Unfortunately, whatever it would be, it is pushed outside the physics’ focus (if I am correct). The vector of physics is about making more precise predictions, not understanding quantization of GR deeper.
It worked for electromagnetism with patches, but didn’t work for gravity.
And gravity is at some point simplified to unknown yet, with the list of ideas.

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Physics, Astronomy & Cosmology / Re: Does gravitational time dilation/GTD really cause gravity?

« on: 23/09/2021 13:14:39 »

Thank you for amendment, Halc.
Right.

The LIGO gravitational waves detection verified that neutron stars merging produced gravitational wave signals during 2 seconds.
The first signal itself was detected as a vibration of the distance between mirrors four kilometres apart. Is it 4 km - for the amplification of the ripples?

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Physics, Astronomy & Cosmology / Re: Does gravitational time dilation/GTD really cause gravity?

« on: 23/09/2021 10:50:06 »

1. Does gravitational time dilation/GTD really cause gravity?
2. "What causes gravity, really"?

1. Gravitational time dilation is a form of time dilation, an actual difference of elapsed time between two events as measured by observers situated at varying distances from a gravitating mass.

Gravity [..] is a consequence of masses moving along geodesic lines in a curved spacetime caused by the uneven distribution of mass.
(Wikipedia)

2. ‘Mass’ here is not necessarily a rest-mass.

Photons have energy, ‘relativistic mass’, which is the source of gravity, not ‘rest mass’. Hence, the energy is the source of gravity.

It is proposed that particles called gravitons cause objects to be attracted to one another. But gravitons have never actually been observed.

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Physiology & Medicine / Re: How Do Isolated Tribes Survive Inbreeding Birth Defects ?

« on: 23/09/2021 09:53:29 »

1. Inbreeding is a problem for tribes with populations near to 50 or below.Tribal customs keep partners' relations far enough.
The European royal lines would be in the endangered group of 50 less.
2. Survivorship bias  has studies on that.
3. They might not be so isolated yet, throughout their history.

16

Technology / Re: Is there a specific sound frequency that discourages birds?

« on: 22/09/2021 13:31:33 »

The exact bird species behavior, ‘crowd’ population, sounds, frequencies, and language differ very much.
It’s better to learn about them from reading and of course bird watching.
I’ve had a fight with sparrows, who made my window as a meeting space. Water gun attacks were first fierce and useless attempts. But finally I have learned that it is possible to keep them away with anything blinking. ‘Anything’ is dangerous because magpies can be there fast. Old CD's worked. No sparrows on my window.

17

General Science / Re: Do you know where the water you drink has been?

« on: 22/09/2021 13:14:17 »

According to what we know about the Earth formation and extraterrestrial influence of asteroids, comets, etc., during our planets' life, the whole water that we have has been always here.
Hence, we drink the same molecules as our not so far ancestors as well hundreds of millions ones.
Human and not human thirsty species ever inhabited the Earth.

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General Science / Re: The sounds of science...

« on: 22/09/2021 12:52:56 »

Human heart beats at 3/4 signature, it is common for waltz (for 500 years), country .. rock.
Think of that the main first sound that we hear even before being born is the heartbeat.

https://www.betamonkey.com/popular-examples-of-music-written-in-3-4/

https://www.izotope.com/en/learn/time-signatures-explained-part-2-writing-songs-in-3-4-and-6-8.html

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General Science / Re: The sounds of science...

« on: 22/09/2021 12:47:18 »

Not a valid vimeo URLSource: https://datadrivendj.com/tracks/brain/
This is representation of seizure.
As Brian says it:
However, as a brief overview, these are the primary brain wave properties I am looking at in the EEG readings and how they affect the music your hear:
Amplitude: is essentially how "tall" the waves are. In the song, when brain wave amplitude increases, more singers are added and the instruments become louder.
Frequency: is how many waves are observed over a given time. When the brain wave frequency increases, the string instruments raise their pitch.
Synchrony: is the simultaneous appearance of rhythmic or distinct wave patterns over different regions of the head over a given time. When the amplitudes and frequencies are synchronous across the whole brain, percussion instruments are introduced.

And that pieces like CZ?
They are this:

Awesome interpretation.
A note might be put, that the following video contains material that might bring thought that be harmful.. )

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Physics, Astronomy & Cosmology / Re: Can someone mine 102 tons of coal in 5 hours and 45 minutes w/ 1935 technology?

« on: 17/09/2021 16:08:07 »

I think this whole thing is a Russian attempt to push workers to work harder and achieve the goal of achievement steam power was an industrial achievement long before 1935 in all civilized countries and coal is the main source of fire.

I think so.
By one local example they pushed the industry with hands. That former united area is reach in coal and workers and its output in the end.
Trying to understand leads to depths of history)