Problem about the definition of gravity

This is the way Physics works....

1) We start with a body of knowledge, a set of laws known to work in a lot of circumstance. This knowledge comes with a set of experiments to test them (if you can't explain the experiment then you don't understand the scientific law).

2) Someone thinks up a new experiment or makes a new observation. Even though the current law makes perfectly predictions in all of the old experiments, this new experiment comes up with a answer that is different than the current law predicts.

3) As soon as this happens, everyone agrees that the current law is no longer valid. Even though the current understanding makes perfect predictions in every experiment except one... that one experiment means that the law is not always true.

4) Someone comes up with a hypothesis. This is a guess, maybe this new law will make a correct prediction for this new experiment (while making correct predictions for all the old experiments too).

5) People test the new hypothesis with all of the old experiments, plus the new experiment, plus any other experiment they can think up. If the new hypothesis makes correct predictions in all of the experiments then it becomes a law. This process involves presenting the experimental results to the scientific community, getting peer review, and inviting everyone else to reproduce the experiments and run their own.

Physics is the body of knowledge that has passed this process. All of the Laws of Physics have passed this process and have been shown to make correct predictions in all of the experiments anyone can think of.

Physics is not "truth". Physics is not "reasonable". Truth and reason are in the realm of philosophers. Physics is only concerned about what the measurments and experiments say. Unfortunately this often upsets the philosophers sense of "truth" and "reason", but this is not the problem of Physics.

Philosophy worries about things as they should be. Physics only measures things as they actually are.

The only reason we accept Einstein's theory of Relativity is because it makes predictions that are confirmed by experiment in every experiment we can imagine. That is it.

Of course there are plenty of limits to Einstein's theory of Relativity, things that our current theory can't explain and things that right now we can't predict. That's just reality.

That doesn't change the fact that I can take Einstein's math, I can make predictions about the movement of astronomical objects or interstellar particles. Then I can fire up my telescope or particle detector and see if my predictions are correct. So far, Einstein has been the best theory we have when it comes to certain types of problems.

I do not necessarily disagree to the nature of your comments but consider your assumptions are not that solid.


@htam9876,
This is the way Physics works....

1) We start with a body of knowledge, a set of laws known to work in a lot of circumstance. This knowledge comes with a set of experiments to test them (if you can't explain the experiment then you don't understand the scientific law).


Well no... Where did the first law come from? One has to have some idea related to understanding so you better respect it I guess. Einstein did not start with the math, he ended up with it is what I would say based on what I know of him and the others. Although intermediate situations do exist.


2) Someone thinks up a new experiment or makes a new observation. Even though the current law makes perfectly predictions in all of the old experiments, this new experiment comes up with a answer that is different than the current law predicts.


Well no... Not necessarily, although it is the trend today it seems. The observation or experiment is not the starting point. One can have an answer before any experimentation, a mathematical confirmation or even any previous experiment. Do you understand the concept of “”rice bowls”, it relates to people protecting the investment they made by getting a “degree”. Understandable but with a need to consider.


3) As soon as this happens, everyone agrees that the current law is no longer valid. Even though the current understanding makes perfect predictions in every experiment except one... that one experiment means that the law is not always true.


Well no... You make it sound like people are robots. In the sense that they “cave-in” at the presentation of mathematical “evidence” or the “experiment”. Consider quarks for instance, a very expensive and elaborate device was build. Then we “see” and “detect” particles... But what do we see? The things observed are not real in the sense that do not really exist by themselves. They are only temporary phenomena (representations of energy exchange) that will never explain the laws of nature, they only provide a mathematical framework for mostly decay and will therefore predict little about the actual structure. Hence the preference for actual understanding and the value of being fairly rigorous about thoughts on any of it. Disregarding a lot of what Science presumes or assumes itself to be.


4) Someone comes up with a hypothesis. This is a guess, maybe this new law will make a correct prediction for this new experiment (while making correct predictions for all the old experiments too).


Well no... Your statement that it is a guess is not accurate. As it can only(!) arise from understanding the situation at hand, thinking about what can and can not be true. Truth is not a Philosophical notion, at least not how you present it. 1 is true, 0 is false. The need to prove anyone wrong or right and to limit or end up with experiments is not that attractive or practical and is actually unlikely to provide knowledge. It is has to be viewed as a secondary notion. If it has to have practical purpose or be used in applications then maybe yes. You are mostly juggling language to suit your outlook.


5) People test the new hypothesis with all of the old experiments, plus the new experiment, plus any other experiment they can think up. If the new hypothesis makes correct predictions in all of the experiments then it becomes a law. This process involves presenting the experimental results to the scientific community, getting peer review, and inviting everyone else to reproduce the experiments and run their own.


Well no... They do not have to reference any experimentation at all. It is(!) law before it becomes anything else. Who cares about peer reviews or “running” experiments, honestly. We need truth. A 1 or a 0 at specific variables. The lack of rigor in thought and experimentations did not necessarily improve much. Einstein did not like what he got although it mathematically presented something that seemed to work. He knew it could not be true. Variables are applied to make things compute.


Physics is the body of knowledge that has passed this process. All of the Laws of Physics have passed this process and have been shown to make correct predictions in all of the experiments anyone can think of.

Physics is not "truth". Physics is not "reasonable". Truth and reason are in the realm of Philosophers. Physics is only concerned about what the measurements and experiments say. Unfortunately this often upsets the Philosophers sense of "truth" and "reason", but this is not the problem of Physics.

Philosophy worries about things as they should be. Physics only measures things as they actually are.


You are making too much out of the “Scientific community”. This world is a open structure. Physics should be truth. In the sense that it should be as close to truth as possible. Reason is essentially math using words, it is only a language difference directed at situations with often have too many or unsolvable variables. You can not really put it in the frame you seem to prefer. https://en.wikipedia.org/wiki/Philosophy Here you go.

Quote: “Physics only measures things as they actually are...” Think about that some more.


@maxdancona
The only reason we accept Einstein's theory of Relativity is because it makes predictions that are confirmed by experiment in every experiment we can imagine. That is it.

Of course there are plenty of limits to Einstein's theory of Relativity, things that our current theory can't explain and things that right now we can't predict. That's just reality.

That doesn't change the fact that I can take Einstein's math, I can make predictions about the movement of astronomical objects or interstellar particles. Then I can fire up my telescope or particle detector and see if my predictions are correct. So far, Einstein has been the best theory we have when it comes to certain types of problems.


Sure, sure, we are not really in a position to accept anything. Truth is truth and it is forced upon you in a way, if you can prove it afterwards and “accept” it is not actually relevant. As you only confirm it is, Philosophy in your lap. Now read about what Philosophy actually is and how it is defined. https://www.ox.ac.uk/admissions/undergraduate/courses-listing/physics-and-philosophy Here you go.

Possibly I will get back to you with some more thoughts or math. After some more Philosophical (and mathematical) rigor.

Piggy’s definition for physics is:
Physics is an elephant;
Physicists are those guys “touchy and feely”.

Piggy hereby provides a bit more humble opinions for reference to those guys who are willing to touch the elephant in an alternative way.
Okay, this post is a bit odd.
First, again piggy invites guys to take a look at the what coffin box from what CN said in piggy’s thread in PHF.
https://physicshelpforum.com/threads/the-game-of-match-sticks.16181/post-50090
If you think that piggy has been defeated by the what coffin box from what CN in PHF USA in 2020, please ignore what I am talking in this post. Thank you.
………………………………………
Supplementary stuff to the chapter “time vs time, touchy and feely”:
In general words, the internal energy is E = hγ, γ is the frequency of the circle kind standing wave (simplified model). It is also applicable to the released photon.
The Time - Energy equation is △t ∝ E. Then, △t ∝ γ. This could be called the Time – Frequency equation. It’s the equation accompanies the Space – Frequency equation r ∝ 1 / γ ahead.
If γ is the frequency of a specific and stable circle kind standing wave (simplified model) or released photon, we can make use a proportionate constant k. Then, the Time – Frequency equation could have a specific form: △t = k γ. In vivid imagination, it means time is the pulse of everything in cosmos.

If γ = 0, then, △t = 0. It means if there is nothing existing, there is no time.
If γ changes, then, △t changes too (the criterion of unit time changes).
Wave is ever travelling, no matter in a circle or in a straight line, the pulse is ever bumping, so, time is ever flowing ahead.
The proportionate constant k could be either positive value or negative value. For convenient sake, we use positive value. The frequency γ is positive value, so, △t should be positive value too. That’s to say the mathematical symbol “- t” is meaningless in physics.
We use a clock not to measure time but to simulate time or say to simulate the pulse: tick, tick and tick…the conception of time generates. We use one “tick” of the clock to simulate one “bump” of the pulse, then, we set up a criterion for unit time: △t = 1 second.
The frequency γ ∝ E, it can reflect the basic property of time: △t ∝ E.
(This is time associated with 3D physical space.)

The issue of “simultaneity” actually is an issue about logic rather than about the physical property of time.

Liqiang Chen
Jan 23, 2021
Piggy has been absolutely defined by the local dark lords of the Jiangmen city and who who of the Class 914 of the No1. Middle School of Xinhui as a semi – half payment watchman in their small business log long ago. That means they has defined piggy’s γ = 0. Bounce…
给他江门地方黑恶势力钟永康集团及新会一中九一四班谁谁一个超文革赛阎王光荣称号快快全世界全宇宙打靶啦。当今时代，全世界没有什么人能够值得如此殊荣。呵呵

If Piggy wants to talk a bit a bit more about physics here. It should be:
Modern physics is already something heavy accumulated and hard to go bad. Perhaps even G* is not able to pull it out of the mud pit.

I just want to make sure that no one is confused.

What you are saying in this thread has no relation to real Physics. I am defining "Real Physics" as what we have learned through study and experiment and is taught in universities.

Maybe piggy should choose another term than "Physics". Using the same word for two completely different things is confusing.

Do you mean you can swear to cosmos that you can represent cosmos?
Okay, from now on, please ignore all of my posts. Thank you. And piggy will ignore all of your posts too.
Because, WE ARE JUST TRYING TO TOUCH THE ELEPHANT IN DIFFERENT ANGLES. You can't understand the philosophy of touching the elephant, which is the power of development of science.

No. We are not touching the same elephant.

Physics is a well defined process where every theory has to be tested through repeatable experiments. There is a strong expert Physics community and a set of knowledge that is taught in Physics classes.

What you are describing is something different than Physics. You should call it something different so people won't get confused.

If you write posts about elephant touching, I will likely stay away. When you confuse what you are doing with Physics, you are inviting me to comment on what Physics actually means.

If you want to learn about elephants, I recommend you talk to a biologist or zoologist who has studied elephants. If you want to become an expert in elephants you would enter a university and study elephants.

There is no need to wallow in the mud blindfolded to learn about elephants (or Physics). That is just silly. You might learn a little by visiting elephants (I would suggest not wearing a blindfold).

But human beings have been studying elephants for centuries. There are experts in the behavior of elephants, the genetics of elephants, the life cycle of elephants, the diet of elephants. You learn all of these things by sitting down in and studying the topic. Sitting around and philosophizing about how elephant should be without actually studying elephants is a silly waste of time.

Why not go take a class?

Up to this date, there is still somebody trying to talk what quark theory in front of piggy, piggy just wonder whether that guy is an idiot...

Piggy is right about the elephant but it is Philosophy who do the "touchy - feely".

Well... you can learn about elephants but you can not prevent them from going extinct.

yes, the elephant of physics is going extinct due to some stubborn guys.
When the mobile phone is going from1, 2, 3, 4G to 5G in a few years, the elephant is still crunching what quark what QFT decades ago.

Once upon a time, one former classmate of the Class 914 of the No. 1 Middle School of Xinhui said: “ah LiQ*, you lag far behind the era…”
Piggy agrees with his humble opinion very much. When some guys have bounced ahead to talk 6789 …dimensions, piggy is still here doing some research on the 3D space. There is an old Chinese saying: the tall building is based on the ground.
When a guy tries to talk what physics and what universe, piggy’s humble opinion is that he should understand the physical property of 3D space and the physical property of time associated with it first. Otherwise that guy sounds like “a tower floating on the air (空中楼阁)”.

Actually, piggy temporarily has no idea how to define gravity. I just analyzed the physical property of 3D space and the physical property of time associated with it.
Piggy encourages guys to touch the elephant in your own way (not necessary following pig’s idea) to break through the monopoly of the so called “standard model” which is absolutely the conspiracy of some people to set up a church on science.
Piggy will extend the conception of space from 3D to 4D in the philosophy forum. Welcome those guys who are willing to touch the elephant in an alternative way to go ahead with piggy.

Thank you, guys.
给他江门地方黑恶势力钟永康集团及新会一中九一四班谁谁一个超文革赛阎王光荣称号快快全世界全宇宙打靶啦。当今时代，全世界没有什么人能够值得如此殊荣。呵呵

That's fine... I do wonder why a Philosopher would use the term 4D.

If you are going to use science sounding words, you should use them in the scientific way. If you are going to do philosophy you should invent your own words.

Let's talk about the definition of gravity from a Physics perspective. In Physics, any definition is based on experiment.

1) 10,000 years ago Ogg Ugthurd of cave #39 let go of a rock with nothing beneath it. The rock fell to the ground. He repeated this experiment and it was consistent. That was first definition of gravity. You drop things, they fall. This is a perfectly good definition of gravity. Ancient languages had words for gravity (including the word "gravitas").

2) Galileo calculated the times things fell from different heights. He did a bunch of experiments with buildings and ramps. He noticed that the time it took to fall dependent on its height was a quadratic function. This was a better definition of gravity.

3) Newton had a cool idea. He wondered if gravity that made things fall was also responsible for the orbits of planets. He did the calculations, and then compared it to the orbits of the planets as overserved. This was his experiment , the calculations matched. This was a more general definition of gravity.

4) People did more experiments with Newton's laws including predicting Halley's comet. The experiments worked. That was cool. People used Newtons definition of gravity to build things including things that fly.

5) People made better measurements and measured the orbit of Mercury. Oh ****! Mercury's orbit doesn't follow the prediction from Newton's definition of gravity.

6) Einstein came up with a new set of ideas... space and time are relative. He develops the math around this and runs the experiment by predicting the behavior of Mercury. It works.

7) They do a bunch of experiments through the years... making astronomical predictions which they confirm. Making predictions in particle experiments which they confirm. They use this to build GPS satellite's and plan space flight.

8) Scientists have been saying... wouldn't it be nice if gravity were unified between Relativity and Quantum Mechanics (another branch of Physics developed through experiment). There is a bunch of mathematics done a bunch of experiments done. People are still working on this problem.

In Physics, each definition of gravity gets more specific, more advanced, more generalized. The ideas get more powerful and complex. Now you need 5 or 6 years of college to master to mathematics just to understand the latest theories.

In truth, Ogg's definition of gravity is perfectly sufficient for almost all your daily life. When my daughter dropped a glass on the floor, I could explain it. Newton's definition is perfectly sufficient for designing airplanes, or predicting the path of a baseball, or explaining the orbit of the Moon.

Any of these definitions are based on experiment. If you don't understand the experiment and the mathematics behind it, then you don't understand the Physics.

That's how Physics works.

Obviously, my threads are not suitable for such ultimate stubborn guy as you. They are for the prospective researchers. haha
Stop disturbing our normal research, please. Thank you.
Trying to be an obstacle in the development of science is not good for the world and even for yourself.
In piggy’s eye, you are just a crazy dog suffering rabies. Understand?

What does the word "research" mean to you.

It seems to be a combination of making stuff up, and reading random pages on the internet.

The word research has a very different meaning to real physicists.