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Physics, Astronomy & Cosmology / Re: Is Coriolis force real?

« on: 27/06/2020 00:02:09 »

Hello

I am confused by Coriolis force.

Is it real? Does it really act on objects?

I read that it is not a real force however how can it then be a result of earth's movement onto objects and not be a real force?

The earth's movement exerts force on the objects on the planet and it supposedly creates and maintains their kinetic energy in respect to the earth's rotation.

Thanks!

It's among a class of forces called inertial forces[/b]. Before Einstein they were referred to as pseudo forces. After Einstein created general relativity they were called inertial forces and looked at as real forces. At least it was looked at byh Einstein that way.  Some modern relativists look at it that way, such as D'Inverno.

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Physics, Astronomy & Cosmology / Re: What is Time? If there was no light would Time cease to be?

« on: 21/06/2020 05:44:45 »

The definition: "time is what a clock measure" is circular since a clock has to be calibrated, ...

Wrong. A clock need not e calibrated. It can merely be built and used it's primary time interval as the unit of time. Do I need to explain what a primary time interval is? Think about a pendulum clock.

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Physics, Astronomy & Cosmology / Re: What is Time? If there was no light would Time cease to be?

« on: 20/06/2020 21:38:16 »

My definition only implicitly requires the concept of time.

I’m fascinated by the idea that the concept of time is “only implicitly” required.  Does that mean that your definition does not require a time concept?  If so, how does it work if any movement/change is involved?

That's the main problem with his and others definition. It requires the concept of motion/change which are defined in terms of time. Thus it's a circular definition and fails as one. I.e. time is defined in terms of motion/change which is defined in terms of time.

There's a book called The Philosophy of Space and Time by Hans Reichenbach, Dover Pub. which some might find interesting to read.

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Physics, Astronomy & Cosmology / Re: What is Time? If there was no light would Time cease to be?

« on: 20/06/2020 19:56:46 »

Thanks, also, for offering to be there if when I run into problems.

It's a pleasure. I'm here for you anytime my friend.

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Physics, Astronomy & Cosmology / Re: What is Time? If there was no light would Time cease to be?

« on: 20/06/2020 18:41:48 »

My definition only implicitly requires the concept of time. It is my contention that implicit reference to the object being defined is allowable.

Allowable by whom? What on God's earth does it mean to be allowable in defining things in physics? All you've done is to state a warm fuzzy feeling of what you think time is measured by. That's identical to saying that time is what measured by a clock. I've already mentioned that on an occasion or two.

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Physics, Astronomy & Cosmology / Re: What is Time? If there was no light would Time cease to be?

« on: 20/06/2020 18:37:26 »

As you also say Pete, it also leads to the confusion between the definition of the phenomenon and the definition of the measurement. That confusion leads to some very illogical conclusions not least of which is the title of this topic.

Here's a nice coincidence for you. I just received I book I ordered from Amazon called Graduate Methods of Classical Mechanics y V.I Arnold, Springer, 1989. From page 2

The text refers to the following as one of three elements of the Galilean structure
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Time - A linear mapping R^4 --> R from the vector space of parallel displacements of the real "time axis."
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 I don't consider this to be a definition of time though since that element does not tell us what R^4 is or what the "time axis" is.

Newton took time and space to be well-known concepts not in need of definitions.

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New Theories / Re: Why is there a maximum speed of light?

« on: 20/06/2020 15:41:50 »

Here's why:

Because photons are made of Riemann Spheres and being the same as space, photons experience a resistive force that cancels the propelling force just at the speed of light.

You've done nothing to provide proof of your claims.

e.g a photon isn't a sphere. In  fact nothing in nature is a geometrical object. They merely have the shape of a geometrical object. Plus the correct claim, if correct at all, is that a photon has the shape of a sphere. NOT a Riemann sphere.

The only thing that is given the name "photon sphere" is the sphere of photons which are in a circular orbit about a black hole at a certain radius.

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Physics, Astronomy & Cosmology / Re: What is Time? If there was no light would Time cease to be?

« on: 20/06/2020 14:50:24 »

I'm certainly not qualified to comment on the maths in this paper, but just from reading the abstract, and looking a little beyond, I have to wonder about the possible translation from mathematical "reality" to any physical demonstration.  I look forward to further developments.

You will never see me define something in an large article. Defining something like time, if its actually possible. takes only a short paragraph.

Take a look at - http://www.exactlywhatistime.com/
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We can measure time extremely accurately, but it is very difficult to define and explain exactly what time actually is
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What taluma1 is trying to do is state what time is by providing a specific example of a clock. Measuring something does not tell  you what it is.

ps - I wasn't going to post again  since I knew they'd be ignored but in this case I felt I had to speak up. Anything else, Bill, I'll PM you.

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Physics, Astronomy & Cosmology / Re: What is Time? If there was no light would Time cease to be?

« on: 19/06/2020 03:40:06 »

That post is wrong.

Is defining time using particles with fluctuating space as input wrong?

Yes.

And your reason is ... ?

Same as held by any physicist, i.e. time is defined as what a clock reads. This is not a good definition because when you get into the details of what a clock is you end up with a circular definition.

See - http://www.exactlywhatistime.com/physics-of-time/

Your definition depends on the concept of fluctuation which in term relies on what fluctuation means. I was hoping to avoid getting into a debate about this since they never end. I'll just leave it here and point you to SR textbooks that you trust.

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Physics, Astronomy & Cosmology / Re: Do our thoughts have mass?

« on: 18/06/2020 20:18:07 »

Why is that? I myself believe that thought processes require changes of a state but I don't see how that means changes in energy level.

Check out reply #5 in this thread, specifically:

Landauer's Principle calculates the minimum energy to change a bit of information. At room temperature, it's about 0.0175 eV.

We can assume that our thoughts result in changes to the state of neurones, which can be interpreted as a change in information. So there must be some minimum energy consumption due to our thoughts.
...
See: https://en.wikipedia.org/wiki/Landauer%27s_principle

I don't understand why you're associating thought with information. Please clarify for me. Thanks.

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Physics, Astronomy & Cosmology / Re: What is Time? If there was no light would Time cease to be?

« on: 18/06/2020 18:11:17 »

That post is wrong.

Is defining time using particles with fluctuating space as input wrong?

Yes.

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Physics, Astronomy & Cosmology / Re: Do our thoughts have mass?

« on: 18/06/2020 14:38:19 »

Just a few thoughts, some of which may already have been addressed.

1. Thought processes required energy.

Why is that? I myself believe that thought processes require changes of a state but I don't see how that means changes in energy level.

(to be deleted later
0 ....the min, so might it be distinguished from activity of the brain?
4. There are two schools of thought here: monism and dualism.   
5. Monism holds that the mind does not exist as an entity that is in any way separate from the brain.
6. Dualism is the belief that the mind cannot be reduced merely to brain activity.
7. Dualism is often seen as implying the existence of a supernatural realm, but is that necessarily correct?
8. Are monism and dualism diametrically opposed, or are there shades of difference between the two?
9. Would these be akin to the shades of difference between death and life in the case of Schrodinger’s cat? 

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Physics, Astronomy & Cosmology / Re: What is Time? If there was no light would Time cease to be?

« on: 18/06/2020 14:16:33 »

It can be defined. See post 247 under this topic.

That post is wrong.

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Just Chat! / Re: Should it be legal to have sex in a hospital?

« on: 18/06/2020 12:06:19 »

Should it be legal for patients to have sex with their wives, girlfriends or paid for company?

Under certain circumstances, sure. E.g. if a patient is about to have chemo therapy is not allowed to leave the hospital them absolutely. Its possible that the chemo might destroy the ability to create life and if the two people want to have a child then this might be the last chance to do it. The chances are small for it to happen and complications might arise from the chemo it' better than nothing.

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Famous Scientists, Doctors and Inventors / Re: Who is the father of physics?

« on: 18/06/2020 06:25:40 »

sanu asked the Naked Scientists:
   
Who is the father of physics?
What do you think?

Galileo Galilei is widely referred to as the father of physics. Isaac Newton, Albert Einstein are known as the Fathers of modern Physics.

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Physics, Astronomy & Cosmology / Re: What is Time? If there was no light would Time cease to be?

« on: 18/06/2020 06:09:17 »

Time cannot be defined. It's a primary concept like space. We can only then provide operational definitions for space and time intervals: measure time intervals with a clock and space intervals with a rod.

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Physics, Astronomy & Cosmology / Re: Do our thoughts have mass?

« on: 18/06/2020 05:47:19 »

Someone by the name of 'Mr Sponge' has messaged in with this question:

Do our thoughts have mass?

Can anyone answer?

I'd hazard to suggest that this all depends on what it means to think. Perhaps different ways of thinking gives different values. E.g. There is energy changes in the human brain which are associated with different thought changes. This might be associated with changes in mass through the relation delta E = delta mc^2. However there may be different (alien?) brains for which this is not true.

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Physics, Astronomy & Cosmology / Re: What is Time? If there was no light would Time cease to be?

« on: 11/06/2020 12:26:54 »

Apples in Geezer's garden  are their quantity, but motion is not quantity of motion. Because the quantity of apples can decrease or increase.  Quantity of motion only increases.
 Here I am wrong,because quantity of  created apples only increase.

Quantity of motion is defined to be momentum in physics. In physics time]/i] is undefined as being intuitively known to all to all observers.

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Physics, Astronomy & Cosmology / Re: How does static electricity work?

« on: 05/06/2020 12:41:01 »

The recommended way to discharge yourself to Earth is through a resistor of several hundred kilohms to a Megohm.

That's so you don't electrocute yourself with a high current. You are neither an electric appliance or an electric circuit. High current destroys circuits. There's a good reason to ground circuits as you may know.

I'm tired of this thread. Think what you want but don't come asking questions if you won't accept the answer - From a legitimate source like a  physics text.
This limits the discharge current to something that humans can't feel - and also won't damage sensitive electronic components.

Don't use a single 1MΩ resistor from the local electronics store - they arc over at high voltages. Put 10x 100KΩ in series for better protection against high voltages.

I just measured the resistance between the front and back door handles of my house,
It's about 400 Mohm.
So, about 200M per door handle.

How did you measure that? My multimeter only goes up to 10 MΩ - and the leads aren't nearly long enough!
[/quote]

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Physics, Astronomy & Cosmology / Re: How does static electricity work?

« on: 05/06/2020 10:31:57 »

The doorknob spends 24/7 connected to ground through the bulk and surface resistivity of the door, so it is reasonable to assume that it is at earth potential first thing in the morning. You could measure its resistance to true earth and it is unlikely to exceed a gigohm

The door is not a conductor so the doorknob is not grounded and therefore the doorknob can have static charge built up upon it.