Ciro Santilli @cirosantilli 37

A law of physics is Galilean invariant if the same formula works both when you are standing still on land, or when you are on a boat moving at constant velocity.

For example, if we were describing the movement of a point particle, the exact same formulas that predict the evolution of $x_{land}(t)$ must also predict $x_{boat}(t)$, even though of course both of those $x(t)$ will have different values.

It would be extremely unsatisfactory if the formulas of the laws of physics did not obey Galilean invariance. Especially if you remember that Earth is travelling extremelly fast relative to the Sun. If there was no such invariance, that would mean for example that the laws of physics would be different in other planets that are moving at different speeds. That would be a strong sign that our laws of physics are not complete.

The consequence/cause of that is that you cannot know if you are moving at a constant speed or not.

Lorentz invariance generalizes Galilean invariance to also account for special relativity, in which a more complicated invariant that also takes into account different times observed in different inertial frames of reference is also taken into account. But the fundamental desire for the Lorentz invariance of the laws of physics remains the same.

Most commonly known as a byproduct radioactive decay.

Their energy is very high compared example to more common radiation such as visible spectrum, and there is a neat reason for that: it's because the strong force that binds nuclei is strong so transitions lead to large energy changes.

A decay scheme such as Figure "caesium-137 decay scheme" illustrates well how gamma radiation happens as a byproduct of radioactive decay due to the existence of nuclear isomer.

Gamma rays are pretty cool as they give us insight into the energy levels/different configurations of the nucleus.

They have also been used as early sources of high energy particles for particle physics experiments before the development of particle accelerators, serving a similar purpose to cosmic rays in those early days.

But gamma rays they were more convenient in some cases because you could more easily manage them inside a laboratory rather than have to go climb some bloody mountain or a balloon.

The positron for example was first observed on cosmic rays, but better confirmed in gamma ray experiments by Carl David Anderson.

This technique is crazy! It allows to both:You actually see discrete peaks at different minute counts on the other end.

It is based on how much the gas interacts with the column.

Detection is usually done burning the sample to ionize it when it comes out, and then you measure the current produced.

The procedure remind you a bit of gel electrophoresis, except that it is in gaseous phase.

Technique widely used to measure the size of DNA strands, most often PCR output of a region of interest.

A simple sample application is gel electrophoresis alelle determination.

The variables of the Lagrangian, e.g. the angles of a double pendulum. From that example it is clear that these variables don't need to be simple things like cartesian coordinates or polar coordinates (although these tend to be the overwhelming majority of simple case encountered): any way to describe the system is perfectly valid.

In quantum field theory, those variables are actually fields.

One of the most beautiful things is how they paywall even public domain works. E.g. here: www.nature.com/articles/119558a0 was published in 1927, and is therefore in the public domain as of 2023. But it is of course just paywalled as usual throughout 2023. There is zero incentive for them to open anything up.

Ciro Santilli controls the following accounts.

With non-trivial activity:

Trivial or no activity:

Profiles without URLs (OMG...):

Accounts in Chinese websites. These accounts might be banned or altered or offer other limitations, so Ciro only communicates briefly through them. All communication through those channels should obviously be assumed to be compromised:

Accounts in Russian websites:

Dead websites:

OK, the Good film tag might imply that you are a Sinophile.

The adaptation is very loose.

To get an intuition for it, see the sample computation at: en.wikipedia.org/w/index.php?title=Ackermann_function&oldid=1170238965#TRS,_based_on_2-ary_function where $S(n)=n+1$ in this context. From this, we immediately get the intuition that these functions are recursive somehow.

An optical multiplexer!

Now let's try and use the trained ONNX file for inference on some manually drawn images on GIMP:

Note that:

We can try the code adapted from thenewstack.io/tutorial-using-a-pre-trained-onnx-model-for-inferencing/ at lenet/infer.py:and it works pretty well! The program outputs:as desired.

We can also try with images directly from Extract MNIST images.and the accuracy is great as expected.