# can't_think_of_a_name

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1. ## Simultaneous waves question 1.24

Go to the link below and click on page 49 and question 1.24. https://scholar.harvard.edu/files/david-morin/files/relativity_chap_1.pdf So assuming I am understand the question correctly Bob and Alice have the same location in both frames. Event 0 everything is 0. event 1 I assume both Alice and Bob are at the same location for every location. So I am just doing the calculations once for Alice's frame for Alice and Bob's frame for Bob. I am not sure if the question asked it but I also did prime frame for Alice and Bob. gamma = 2 v = .866c t = 1 sec I go d = vt = (1 s)(.866c) = .866LS (for lorentz transform) Then t = 2 I could do the calculation or mulitply everything by 2. For t = 3 multiply by 3 etc Now to find t' for event 1 t' = gamma (t -xv /c^2) t' = 2(1 sec - (.866LS)(.866c) ) t' = .5 sec. Now to get event 2 variables multiply time by 2 to get event 3 multiply 3. Here is my basic formula t_event_number = t_1_or_t'_1 (event_number) t_event_number = t_1 t'_event_number = t_1' Let me show an example t_1' = .5 and t_1 = 1 While, event number = 0 - infinity Is this correct?
2. ## Could mental illness be caused by gut microbes? For example could schizophrenia be caused by hallucinogenic gut microbes ?

I remember reading that gut microbes could affect mental health. I was thinking this could be similar to H pylori. Has anyone tested the hallucinogenic gut microbe idea before? How are gut microbes mapped? https://massivesci.com/notes/antidepressant-gut-health-bacteria/ https://www.inverse.com/mind-body/scientists-explain-link-between-depression-and-the-gut
3. ## Whenever I turn on the camera my webcam starts blinking or IOW flutterung. This happens when the webcam is on.

By blinking I mean the screen seems like it is blinking. The webcam is built into the pc. I did a clean install in windows 10 then the webcam started acting up. I did an avira virus scan and even an online set scan and malwarebytes and everything came back negative. I also loaded some files from my usb and scanned my usb with malwarebytes and avira and nothing came back. I even tried the method from the link below. The 4th method didn't work because I couldn't create a new file. Can someone help fix my webcam and make sure I don't have a virus etc? The only things besides antiviruses's I downloaded were apps in firefox, which were privacy badger, https everywhere, Dencentraleyes and ublock origin. Specs below Thanks
4. ## app question

Do you know the name of the store or apps so I could see what they are doing? Also sensors are expensive. I was thinking everyone who uses the app has a phone. So each phone would have a code that uses something like Bluetooth or NFC and send out a random generated code that isn't ever reused. During the rental of the item the code would be registered and the return would be registered. But this relies on good faith. Most people will follow good faith but a percentage won't. A friend suggested a rating system. I guess you could ban people below a certain star. But would that work? Well I can think of a few ways around that. 1 only make money on the advertising on the platform. Can you make money off of that? 2 at a later date create an subscription fee. I assume you could create a subscription fee at a earlier date but would that work? 3 create a retail store front where everything is stored. I don't like 3. Is there anyway people would be okay with fees without cutting out the middle man as in me. Thoughts?
5. ## Is it okay if I summarize special relativity in my own words and examples and someone reviews it to make sure I didn't make any mistakes?

Ignore the post right ahead of this. So what your saying is the Lorentz transform doesn't change form a stationary frame to another stationary frame? It seems like you have to start with L = L'/gamma in whatever reference frame you are in. Why can't you start with L' = L gamma? Does the Galilean transform still work in special relativity in changing from Bob's stationary frame to Alice stationary frame? What is now confusing me is why the speeds in Bob's frame doesn't go from .983c to Alice frame -.0983. is this where I use Einstein velocity addition formula
6. ## app question

I have come up with an idea. Without going into too much detail the idea is to rent products in your area. I would create a mobile app. People would rent the product. Each transaction I would make money off of. The problem I am having is how would I confirm the transaction went through and confirm the product was returned? Also I know the basics of coding but never made a mobile app or anything really. I was thinking of starting off as an apple app but eventually developing for android. Is there a way develop for both android and apple? One problem is copycats could easily be created. Do you think the best way to avoid copycats is to get funding, assuming I could get? The app couldn't really be used until after covid is cured so it is far off. Also how do you build an app that doesn't crash when it has too much traffic? Is it very hard to get funding? I am also planning on partnering with someone I assume I should pick someone in the same city. Hopefully I didn't give away the idea. Does anyone know any good languages to create it in? I just realized this could go in computer science area.
7. ## Is it okay if I summarize special relativity in my own words and examples and someone reviews it to make sure I didn't make any mistakes?

So what your saying is the Lorentz transform doesn't change from a stationary frame to another stationary frame? It goes from stationary object to moving object, but the moving object doesn't become stationary it stays moving. This always works from moving object to stationary object. Does the Galilean transform still work in special relativity in changing from Bob's stationary frame to Alice stationary frame ? What is now confusing me is why the speeds in Bob's frame doesn't go from .983c to Alice frame -.983c. Is this where I use Einstein velocity addition formula?
8. ## Is it okay if I summarize special relativity in my own words and examples and someone reviews it to make sure I didn't make any mistakes?

I uploaded a picture just to make this clear for me. I think I got the correct answer. But I have 1 question. L = 4.93 in Bob's frame. In Alice frame L' = 4.93. Therefore I apply Length contraction. L = L' / gamma. This makes L = .82. Why doesn't L' in Bob's frame become L = 29.58 in Alice's frame? I know moving objects are smaller from a stationary observer. But isn't stationary object bigger for a moving observer? I apologize if this repetitive. Ignore this picture below.
9. ## Is it okay if I summarize special relativity in my own words and examples and someone reviews it to make sure I didn't make any mistakes?

I mean d = L.
10. ## Is it okay if I summarize special relativity in my own words and examples and someone reviews it to make sure I didn't make any mistakes?

I Calculate the length for Alice in Alice's frame I get d = vt Then I calculate d = vt = (-.986c)(5 years) = -4.93 LY. Alice sees the planets moving so I go L=L'/gamma. -4.93/5 = -0.986 LY The part that was confusing me is the difference between d = vt and L=L'/y. I thought d = vt and L=L'/y are the same. How are they different? Thanks gamma should be 6 but ignore that just go with 5.
11. ## Is it okay if I summarize special relativity in my own words and examples and someone reviews it to make sure I didn't make any mistakes?

No. If I am not mistaken there length needs to be the same to maintain symmetry for stationary Bob and stationary Alice. So how do I switch frames? Just to confirm L_stationary = L_moving / gamma. That doesn't switch frames? I assume the problem is the - sign.
12. ## Is it okay if I summarize special relativity in my own words and examples and someone reviews it to make sure I didn't make any mistakes?

Maybe I am just really confused but I have Bob's frame and Alice's frame. In Bob's frame I have Bob who is stationary and Alice who is moving. In Alice's frame I have Alice who is stationary and Bob who is moving in the opposite direction. Length contraction deals with either Bob's frame or Alice frame but it doesn't switch from Alice's stationary frame to Bob's stationary frame. To answer your question exactly "Alice in Bob's frame" I just mean Alice is moving and Bob is stationary.
13. ## Is it okay if I summarize special relativity in my own words and examples and someone reviews it to make sure I didn't make any mistakes?

In my first post I just want to confirm length contraction in special relativity at a later date I will post my entire summary of special relativity. It is a work in progress. I travel to a planet from earth it takes 5 years. Bob is located on earth. Alice is moving at v = .986c on a spaceship to the other planet. If I want to know the length for Bob in Bob's frame d= vt = (.986c)(5 years) = 4.93 LY If I want to know the length for Alice in Bob's frame. L = L'/ gamma = L' = (L) (gamma) = L' = (4.93)(5 years) = 29.58 LY If I want to switch velocity I use Einstein''s velocity addition formula and I get -.986c for planet earth and the other planet. My main question is why time for Alice in Alice's frame = 5 years. If I am not mistaken. Then I Calculate the length for Alice in Alice's frame I get d = vt Then I calculate d = vt = (-.986c)(5 years) = -4.93 LY Then I calculate the length for Bob in Alice's frame . L' = (L) (gamma = -29.58 LYLY. So to summarize I have 2 frames Alice and Bob and 2 measurements in each frame a moving and stationary frame that I need to calculate. If I made any mistakes please correct me if I didn't then tell me?
14. ## what is the difference between speed(units of c) and the Reciprocal in special relativity? Link below for reference

I also have one more question if I have c+t =g. If I want to move g to the left of the = sign. I don't care how pointless this is. I go c+t-g = 0?
15. ## what is the difference between speed(units of c) and the Reciprocal in special relativity? Link below for reference

Hopefully the last question about basic math. Does √1 = 1^-1. Also I can go √1^2 = 1. Are there any other ways to remove a square root?
16. ## what is the difference between speed(units of c) and the Reciprocal in special relativity? Link below for reference

1 / Gamma = √ (1 - v^2) c^2/ c^2 is the same as 1 / Gamma = √ (c^2 - v^2) c^2/ c^2 shouldn't this give c / Gamma = √ 1 - v^2 if I do it my way. Or is that just not how algebra works?
17. ## what is the difference between speed(units of c) and the Reciprocal in special relativity? Link below for reference

I apologize for asking basic question I guess when I was originally in school either I didn't pay attention or wasn't taught properly. I assume the former but I can't be certain. I appreciate the help on basic questions. why is this wrong? Gamma = 1 / √ (1) - v^2 / c^2 = 1 / Gamma = √ 1 - v^2 c^2/ c^2 = c / Gamma = √ 1 - v^2 +v^2 = c + v / gamma = √ 1 = switch the c + v to v + c = v + c / gamma = √ 1= v + c / gamma = √ 1 = v + c gamma / gamma = √ 1 (gamma^2) = v + c -c = √ gamma^2 = v = √ gamma^2 - c or 1 / Gamma - c^2 = √ 1 - v^2 / c^2 - c^2 = 1 / Gamma - c^2 = √ 1 - v^2 = 1 + v / Gamma - c = √ 1 - v^2 + v^2 = 1 +v / Gamma - c = √ 1 =switch the 1+ v to v + 1 = v + 1 / gamma - c = √ 1= v + 1 gamma / gamma - c = √ 1 (gamma) = (v + 1) -c / - c = √ gamma -c^2 = - (v+1) = √ gamma -c^2 = -v -1 = gamma -c^2 = -v = √ gamma^2 - c^2 + 1^2 = - v / - = √ gamma^2 - c^2 + 1^2/ - = v = √ gamma^2 - c^2 + 1^2 / - = v = √ -gamma^2 + c^2 - 1^2
18. ## Retrocausality

Okay I am not sure if this is good or bad answer. Worst case scenario the universe does repeat. I Imagine I have pattern red green blue. This pattern repeats red green blue infinitely many times. I can either view the pattern as infinite or finite. Do I really need to count the additional red green blue or can I just view it as one pattern. Just to make it clear red green blue (happens once) red green blue (happens infinite times) I don't need any more information to know the pattern. Its like saying what is the number 1 is it 2/2/2/2 infinite times it doesn't add any information. Of course you can view it as an overly complex infinite pattern or you can view it as happening once. It reminds me of the glass half full half empty. It depends on your perceptive. I wasn't really going for the positive or negative outlook I was just saying both are correct but you can choose how to view it. I apologize if this is a horrible answer. I am no way saying the universe repeats. Feel free to delete this answer if it sucks.
19. ## x^2 +1 -1/k. Is x^2 +1 -1/k = 0 or x^2 +1 -1/k = 1

x^2 +1 +1/k if I move the k to the right hand of the = sign first it can't be zero because k/0. x^2 +1 +1/k if I move the +1 to the right hand of the = sign first it can't be 1 because that would make 0. So what is it 0 or 1? I probably just made a simple math mistake I apologize if this is a stupid question.
20. ## what is the difference between speed(units of c) and the Reciprocal in special relativity? Link below for reference

I meant v = c/ gamma
21. ## what is the difference between speed(units of c) and the Reciprocal in special relativity? Link below for reference

I know I got v = gamma/c. Like stated earlier why does b= v/c give a different answer. I was solving a problem problem 3 A. I used V = c/gamma but they want b = c/v. This confuses me why does one works and not the other? I guess I really didn't explain this well. In my course they never explain the difference. If the link doesn't work I will post the question. From here https://d3c33hcgiwev3.cloudfront.net/_d37cb29a797de375eb7866e695098a79_Wk7_problemsetsolutions.pdf?Expires=1603756800&Signature=SUmoIwTy2VAIs1CfSGO~F7C3BD7lIJKyMQJuedeO4RUqiCeo9HTLJk50r~oKjI6pAFoaSG5p-Pu3FRHuPiNizcGdd6EdCj4Eer1tU4BqbIBsdzW0WjLXxR8E~-5gZx3LDteO6L4ruR80eOQi1EzUdBj8Z9lnXJ6kQuj1fHpJGik_&Key-Pair-Id=APKAJLTNE6QMUY6HBC5A
22. ## what is the difference between speed(units of c) and the Reciprocal in special relativity? Link below for reference

I start with gamma. The part that confuses me is that I want velocity = , from gamma . I get v = c/gamma.(I could have made a math mistake.) It never says I need B = v/c. I know B isn't the correct symbol I am just using it here.
23. ## Lorentz transform equation help, special relativity

Thanks for the prompt responses.
24. ## Lorentz transform equation help, special relativity

Does this imply a computer can't solve non linear equations?
25. ## Lorentz transform equation help, special relativity

This math is beyond my understanding at this point but shouldn't this make it quite easy to solve to nonlinear equations? https://www.quora.com/Is-there-an-algorithm-for-solving-nonlinear-systems-of-equations-akin-to-Gaussian-elimination
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