# TakenItSeriously

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1. ## Corona virus general questions mega thread

According to worldometers.info on 03-22-2020 @12:30 afternoon which is the top site from a google search of “coronavirus numbers” Total Cases: 321,278 Active cases: 211,573 Recovered: 96,006 Deaths:13,629 First of all, I am not a doctor nor am I mathematician. However, I was tested as profoundly gifted at logic in college which means that I have a knack for problem solving. These numbers are based on only what we know as reported by governments around the world. Of course the numbers may not be accurate due to political fudging and of course testing is not anywhere close to 100%. However, it seems to me that the odds of dying after testing positive is not really around 4% as reported by most media outlets. This number seems to be a best possible spin of the numbers i.e. # of deaths divided by total cases: 13,629/321,278 = 4.264% I believe this is the wrong way to calculate the numbers because it includes the 211,573 of active cases which are uncertain as to whether they will result in a recovery or a death. If you test positive and you ask the question: what are the odds of coming out alive when all is said and done then a more accurate prediction should be the number of deaths divided by (the number recovered plus the number of deaths). 13,629/(96,006+13,629) = 13,629/109,705 = 12.49% Now to be fair, there is quite a large lag-time between the number dead to the number recovered because it’s early in a growth dynamic scenario where death generally occurs much more quickly than recovery so we can probably assume the recovery number should be much higher but still, I think the most accurate number should be something like somewhere between 4.3% and 12.5%. Thoughts?

3. ## The Anti-verse is getting attention

Now that I just posited that relativistic effects are directional: Are relativistic effects directional? If that were true and length contraction represents one side while time dilation represents the other side and the top half represents the universe while the bottom half represents the anti-verse. Then, in that case, the full plot of α vs β makes sense as a unit circle: I didn’t want to introduce this plot in the other thread because I didn’t want to suggest that positive/negative α represented directionality. positive/negative β represents directionality. The Penrose diagram shows the role of the anti-verse with black holes.

5. ## Are relativistic effects directional?

That’s what I was trying to do. As I said, I meant to say the sentence was nonsensical as written, not the entire post, and I did say that I assumed it must contain some typos. Edit to add: I apologize for any confusion.
6. ## Are relativistic effects directional?

Janus Theres some confusion here on what was posted that I’d like to clarify before it gets out of hand. First, please refer to this post: When I was saying it was nonsensical I was referring to the particular sentence I quoted, not your entire post. After I posted it, I realized what you must have meant to say.... You used an ambiguous reference of “her” which could have meant Carole or Alice. I assumed you meant Carole’s point of view when I saw you refer to Alice in the same sentence. The problem was compounded when you mistakenly referenced that Alice was catching up to Bob. It’s a minor error, but when speaking in the context of SR, it becomes very confusing and that’s why I said it was nonsensical as written. I waited a while before replying trying to avoid a cross post. Unfortunately you were busy writing a long reply so my waiting only backfired. After rethinking the problem with the corrected sentence I compounded the cross edit with a cross post before seeing your long reply and posted an encapsulation of what I thought you were trying to say. So having said this, is that what you were trying to say, mor or less.
7. ## Are relativistic effects directional?

Edit to further add: So in the corrected context, I think the point you may be trying to make is that all three points of view on the problem tells a very different story which I agree happens a lot in SR. Kind of like the simultaneity thought experiments. So how valid could any conclusion be unless they all meet at some point which is impossible without adding acceleration into the problem. Is that about it? Ugh, cross posted. Sorry, I can take a while wile pondering the problem.
8. ## Are relativistic effects directional?

I assume this contains some kind of typos. I mean I think your saying that Alice’s perspective on Carole’s speed is 0.97561... c and vice versa which I understand without doing the math myself but the rest is nonsensical as written. Edit to add, after reading it a few times more I think you’re trying to say the following: From Alice’s perspective after passing Carole, Bob is receding at 0.8c and Carole is catching up to him at roughly 0.98c. Is that correct?
9. ## Are relativistic effects directional?

Sorry, I think you made a mistake here. From Alices perspective: Alices travel distance on the outbound leg due to length contraction should only be 8 Ly*0.6 = 4.8 Ly therefore her travel time is 4.8/0.8 = 6 years.
10. ## Are relativistic effects directional?

Ok, I got it. For sure acceleration adds a ton of complexity to this problem. BTW it’s not a stable model unless you add a balancing mass on the opposite side of B, say B’ but thats getting a little nit picky. It reminds me of an even simpler model of two astronauts tethered together in flat space. Someone gives them a push and they start spinning apart putting tension on the tether and ending up in a dual orbit kind of like a binary star system. So what happens if you remove the surrounding universe from this model. They would have no reference frame to know that they’re even spinning and it would then seem as if they were just drifting in the void with a strange repulsive force that is pushing them apart. Others would argue that their would no longer be a repulsive force and they would just be floating together in the void with the tether limp between them. The point is that I agree that gravity or acceleration adds a ton of complexity to the problem. That’s why the three observer thought experiment (not mine BTW) was modified to only involve drift speeds taking acceleration out of the problem all together. https://en.wikipedia.org/wiki/Twin_paradox?wprov=sfti1. I will respond to your analysis of that problem next. I set the model up to be equivalent with the TP example you gave initially: Bob’s time on Earth is still 20 years. Essentially Alice’s travel time is 6 years, Carole’s travel time is a symmetrical 6 years so the total is12 years which is 60% of Bob’s time of 20 years. I can’t see how you derived the numbers in your analysis. Can you please clarify?
11. ## Are relativistic effects directional?

I agree, it can become a confusing mess. That’s why I like to break problems down to their simplest forms possible while still considering all relevant variables and points of view. I’m a little confused about what each clock is doing. Is it that the central clock is spinning around at the center point of centrifuge A. Another clock is revolving around the spinning clock at some radius on the perimeter of A A third clock is revolving around a separate centrifuge B and the two circular paths meet up like two spinning gears?
12. ## Are relativistic effects directional?

Damn, I lost my entire last post due to an outage. Hopefully I’m back now. #5 Regarding acceleration. I mostly agree especially with how it plays no role in explaining the time deviation experienced by the twins. Perhaps not as much as with the asymmetry of the other effects. Acceleration, while once accepted as the underlying cause, has since been refuted because of a modified TP thought experiment which removed all acceleration from the problem and you still end up with the same results. It adds a complex asymmetric effect to be sure but it’s irrelevant to the simple form of the problem when using only velocity. You can look it up here: https://en.wikipedia.org/wiki/Twin_paradox?wprov=sfti1 Under Twin Paradox subtitle: the Role of Acceleration. A synopses of the modified version includes three observers Bob at rest on Earth. Alice drifting past the Earth at 80%c on her way to the star 8 ly away. Carole drifting in the opposite direction at 80%c passes the star at the same time Alice passes it. Carole collects Alices information such as travel time, travel distance from the Earth, observations on Bobs time, etc. She then proceeds to Earth and passes all of Alices information as well as her own to Bob and the time experienced by both travelers only adds up to 60% of the time experienced by Bob. #6 I recall the Hafle-Keating experiment using jet airliners and atomic clocks and I agree that it does seem to represent a bit of a conundrum. However, I would question whether the time dilation measured was due to gravity or velocity. For example, I’ve been told that the time dilation calibrated for in GPS satellites is almost entirely due to gravity. I know, different elevations and speeds, but I just get the feeling that gravity still dominated time dilation in that experiment but IDK for sure. In any case, I’ve tried to consider how to adapt orbital information into the TP and it’s just beyond me so I let it drop and left the question to smarter minds to ponder than my own. Now we already agree that time dilation is the cause of the relativistic component of relativistic red shift. So how I would explain the cause behind the relativistic blue shift effect: Using the original example, Alice has just turned around and is headed for Earth. From Bob’s PoV: Alice is racing her own light traveling at 100%c while she is moving at 80%c. Another words it takes the light 8 years to reach Earth while it takes her ship 10 years. Therefore all of her transmissions on the return leg must be compressed into only two years. So this blue shift effect can all be explained by simple lag-time for the light to travel such a distance just like communications in our own solar system. No time dilation involved. However there is still the difference between relativistic blue shift and normal blue shift so what explains this difference. Well, Bob would expect Alices return leg to take 10 years which is squeezed into 2 years. However, after he meets Alice and counts the pings, he sees that there was only 4.8 years of pings compressed into those 2 years. As I mentioned before, the 60% of the time she experienced on her journey home is due to traveling only 60% of the distance due to length contraction. To look at it another way, we agree that: light waves from Alices ship exist in the space between Alice and the Earth. We agree that information is conserved and no waves (or pings) are either inserted or deleted. We agree that from Alices PoV the distance between the Star and Earth is length contracted to only 4.8 ly So what do you think happens to those light waves in length contracted space? The waves themselves must also be contracted...well at least those waves that are received from their sibling. You see the waves that are emanating from Alice’s ship are all part of the ships inertial reference frame. The waves that are emanating from Bob are all part of the Earth’s inertial reference frame. So from Bob’s PoV, the waves transmitted from Alice are length contracted. From Alices PoV, the waves transmitted from Bob are length contracted. Note that the waves coming from their own transponders are always pinging at 1 sec per sec. Another words the waves transmitted from their own transponders are all in each twins own respective inertial reference frame regardless of where they are in space. QED
13. ## Are relativistic effects directional?

The directionality I refer to is the relative type as in moving away from the observer vs moving towards the observer. In the problem from Alices point of view, you calculate length contraction for the distance Alice has to travel (in the direction of motion.) from Bobs point of view he knows the distance is 8 ly but he could calculate time dilation of a receding ship.
14. ## Are relativistic effects directional?

I agree and I’m not trying to say that it does. Strange was the one who was trying to assign meaning to the sign of the Lorentz factor. I only tried to tell him it doesn’t apply that way. Thanks. I’m going to have to get some sleep now. I’ll get back to this later.
15. ## Are relativistic effects directional?

Because I guess he was associating the sign with directionality or something. The Lorentz factor as used in the TP doesn’t require a sign because it’s not a vector.
16. ## Are relativistic effects directional?

This post and the next post is where strange brought it up. I didn’t understand why.
17. ## Are relativistic effects directional?

The directionality I’m talking about in the title is the relative velocity as in moving closer vs moving away or as in relativistic red shift which I link to time dilation vs relativistic blue shift which I link to length contraction. Strange claimed that the kind directionality I was positing wasn't consistent with the math. I showed him why it was consistent. He then accused me of lying and then brought up the signs for the Lorentz factor for some reason. I told him that the Lorentz factor as applied to the TP doesn’t have a sign because its not a vector.
18. ## Are relativistic effects directional?

I really don’t know. Ask Strange, he brought it up.
19. ## Are relativistic effects directional?

Your kidding right? You do realize that when you take the square root of any number you get a positive and negative result right? e.g. √4 = +2 & -2 Besides that the Lorentz factor is not a vector. It doesn't even have units.
20. ## Are relativistic effects directional?

Not at all. From Alices point of view length contraction is calculated for the distance to Alices destination that she is moving towards. From Bob’s point of view her time is dilated as she moves away from him.
21. ## Are relativistic effects directional?

I would add that the math is also consistent from Bob’s perspective as well. Recall that from Alices point of view we apply the factor for length contraction to her destination. From Bob’s point of view, he knows the star is 8 ly away so he would apply the factor only to time dilation not lrngth contraction. T’ = 0.6·(8/0.8) = 6 yr each way.
22. ## Are relativistic effects directional?

Actually it’s consistent. When you calculate the travel time and distance to the destination when traveling at 80%c, for the math to be consistent, you must only apply the Lorentz transform only once. e.g., in this example, the proper distance to the destination is 8 ly. Alice is moving at 80%c D₀ = 8 ly β = v/c = 0.8 the Lorentz factor: α = √(1-β²) = 0.6 So from Alices point of view her length contracted distance is: D’ = αD₀ = 0.6*8 = 4.8 ly Alices travel time is next calculated directly from D’ without using the Lorentz factor: T’ = D’/β = 4.8/0.8 = 6 yr
23. ## Are relativistic effects directional?

Ok, you’re right. That was a bad example. Let me try to explain it another way but first allow me to outline what I think we do and don’t agree on so we can get on the same page. Some of this may be trivial to you but I’m just trying to cover all the relevant bases. Light waves exist in space between source and observer as opposed to the Newtonian view where the SOL is instantaneous. The speed of light is constant to all observers but the frequency of light is frame dependent according to the relativistic doppler effect. If you agree with Janus, the causality of the relativistic component of relativistic redshift can be explained by time dilation. So far we don’t agree on the causality of the relativistic component of relativistic blueshift. Acceleration has been largely refuted by the physics community as the reason for the time deviation experienced by the twins. You think that both length contraction and time dilation are true in moving frames regardless of whether the light source is moving towards an observer or away from an observer. I think that time dilation is only true in frames where the light source is moving away and length contraction is only true in frames that are moving towards an observer. Would you agree with the list above? Please correct anything that’s wrong or feel free to add anything else you feel is pertinent.
24. ## Are relativistic effects directional?

Sure, ok. So the question that needs to be addressed, or the paradoxical perspective is that each twin should have symmetrical views of the other twins time, which is true (the each see the others time at 1/3 normal on the outbound trip and as 3x on the inbound trip) so how can they have experienced different amounts of time? The asymmetry of this problem is the asymmetry of their inertial frames of reference and therefore the asymmetrical results that length contraction of those frames contributes to the problem. Another words, from Bob’s perspective, only the ship, Alice and the rest of it’s contents become length contracted as the moving reference frame which contributes no additional information to their travel time. From Alices perspective, Bob’s inertial reference frame includes Bob, the Earth, the destination of some star that’s 8 light years away, and the distance between the Earth and that Star. So when that inertial reference frame becomes contracted, it shortens the distance she has to travel and therefore the time she has to travel by 60%. Thats why she experiences 12 years compared to Bob’s 20 years. Edit to add: If you can see this solution now and it just seems too obvious to be true, please don’t feel bad because it’s not. Once you fully understand any problem, no matter how difficult, the solution always seems simple in hindsight.
25. ## Are relativistic effects directional?

Ok, I originally misread the problem but these numbers seem fine to me now. From Bob’s point of view, I agree Bob ages 20 years and he sees Alice age 10+2 = 12 years. Just something I’d like to point out about Alices point of view: Notice that you start with the assumption that Alice travels for 6 years on the outbound leg and 6 years on the inbound leg which I agree with but you neglected to say why it’s only 6 years each way. It’s due to length contraction of the 8 light year distance: The Lorentz factor α = 0.6 0.6*8Ly = 4.8Ly each way so her travel time becomes: 4.8Ly/0.8 = 6 years each way or 12 years total. So the reason for the deviation in time experienced by each twin is due to length contraction! Another words Alice had only 60% of the distance to travel from her point of view so it only took 60% of the time to travel it.
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