They had better think fast, because even at 10g acceleration it is going to take over a month for the shuttle to slow down.

 

I am impressed. A variation of this problem set was given to more than 100 students over 4 years and you are only the 2nd person to point this out. However, the ill conceived choice we made in describing direction was neither significant nor brought to bear at any point in the set beyond the introduction. But kudos for seeing this.

You know Bill...the statement in the problem asked stating A, B, East, West and by stating this within the problem meaning there is a 3rd Observer is a practice in Logic as well as Shroaty's Cat in the box.

The problems question and discription of does not indicate that a 3rd observer provided this information and just because this question tells us the specifics of velocity, craft direction...etc...does not provide a Logical basis that just because these specifics are mentioned...that this information is observed.

If you were to site...Well how could we know such details without a 3rd observer and in real life there would have to exist one for this information to be given to us. But if we were to site the Real World...the ability for such craft to obtain such velocities by propulsion or the reality it would take LIFETIMES to accelerate such craft to .9999c safely and without killing the crew would also present itself.

This is a theoretical question designed to task students and just because specifics such as velocity and directions are provided...by Logic...does not dictate a 3rd observer.

Not trying to take anything away from the poster who brought this up...it is a intelligent thought...just not necessarily a reality.

Split Infinity

 

They had better think fast, because even at 10g acceleration it is going to take over a month for the shuttle to slow down.

With distances in this universe measured in the billions of light years, they could have all the time they want.

 

With distances in this universe measured in the billions of light years, they could have all the time they want.

Bill...if these two craft...and let's say for arguments sake...were 1 Billion Light Years away from each other...it would take more time than the Universe will EXIST...for these two craft to accelerate safely to prevent the deaths of all on board both craft to a velocity each at .9999c.

It would take FOREVER AND A DAY...for such craft to slowly accelerate to .9999c...never mind each having to travel a Half Billion Light Years each. LOL!

Split Infinity

 

Bill...if these two craft...and let's say for arguments sake...were 1 Billion Light Years away from each other...it would take more time than the Universe will EXIST...for these two craft to accelerate safely to prevent the deaths of all on board both craft to a velocity each at .9999c.

It would take FOREVER AND A DAY...for such craft to slowly accelerate to .9999c...never mind each having to travel a Half Billion Light Years each. LOL!

Split Infinity

Really.

So, let's take a craft that can accelerate at just 1g. Would that meet your criteria of being a low enough acceleration to prevent the deaths of all on board? So, at that 1g acceleration, how fast will the craft be going after one year?

 

Split, I suspect you don't read a lot of SciFi. Even a really small acceleration, if it is truly continuous, adds up fast. It is very similar to compound interest. Continuous thrust is a lot harder than it sounds, but not unachievable. This is where a lot of the interest for Bussard ramjets and ion drives (not the Hollywood versions) come in.

 

Really.

So, let's take a craft that can accelerate at just 1g. Would that meet your criteria of being a low enough acceleration to prevent the deaths of all on board? So, at that 1g acceleration, how fast will the craft be going after one year?

If a Human Body takes acceleration that produces G-Forces of .1 G every second in a LINEAR FASHION...as there is Angular and other geometric G-Force effects upon the Human Body...but if so Linear...after a minute or so a person will have Blood Flow issues that will effect vision, hearing, heart rate...YOU NAME IT! And that is just at an acceleration producing .1 G's every second.

To accelerate safely over a vast period of time to allow people on such craft to not have Physiological Medical problems...ie...DEATH...such a craft would have to accelerate at .01 G's every second.

Do the MATH...at this rate it will take...FOREVER.

Split Infinity

 

Split, I suspect you don't read a lot of SciFi. Even a really small acceleration, if it is truly continuous, adds up fast. It is very similar to compound interest. Continuous thrust is a lot harder than it sounds, but not unachievable. This is where a lot of the interest for Bussard ramjets and ion drives (not the Hollywood versions) come in.

Bill...LOL! You posted before I could...and YES!...I know about even small G-Force issues upon the Human Body!

Wish I could have got mine out first! LOL!

Split Infinity

 

If a Human Body takes acceleration that produces G-Forces of .1 G every second in a LINEAR FASHION...as there is Angular and other geometric G-Force effects upon the Human Body...but if so Linear...after a minute or so a person will have Blood Flow issues that will effect vision, hearing, heart rate...YOU NAME IT! And that is just at an acceleration producing .1 G's every second.

To accelerate safely over a vast period of time to allow people on such craft to not have Physiological Medical problems...ie...DEATH...such a craft would have to accelerate at .01 G's every second.

Do the MATH...at this rate it will take...FOREVER.

Split Infinity

And what I mean as far as .01 G...every second...what I attempted....POORLY to say is it must remain a CONSTANT .01 G...over the entire period of time or people will start to die.

Split Infinity

 

Split, I suspect you don't read a lot of SciFi. Even a really small acceleration, if it is truly continuous, adds up fast. It is very similar to compound interest. Continuous thrust is a lot harder than it sounds, but not unachievable. This is where a lot of the interest for Bussard ramjets and ion drives (not the Hollywood versions) come in.

Bill...also....9999c is IMPOSSIBLE to achieve using a form of Propulsion. Some might think that given enough time using Nuclear Fission Micro-Detonation Propulsion or using an Ion Drive or other propulsion methods would eventually bring such a craft to .9999c.

Never mind the time issues...the problem remains that the Physical Laws that govern the maximums of reality as far as Kinetic Transference and the Maximum Velocity at which a material in a state of being used as a fuel for propulsion or even the minimum amount of time it would take for Ions used as the propulsion actually leaving the engine or whatever would be considered such depending upon propulsion method....WILL NOT BE VIABLE as far as being able to propel a craft to 9999c.

It is like using a Jet Engine and then using it's afterburners...dumping aircraft fuel directly into the Jet Engine exhaust stream at the edge of the engine exhaust output...to travel faster than the Afterburner Jet Stream is traveling.

So if such an Afterburner Stream is exiting the aircraft at Mach 3.5...and THAT is the maximum possible by the laws of physics that such a stream can travel in this engine construction and fueling...then the aircraft can never go faster than Mach 3.5...or ever even reach Mach 3.5.

In the Space Craft example...by the Laws of Physics in our Universe...there is no method of Propulsion that can bring a craft to the velocity of .9999c.

Thus the answer to surpass this velocity is to not use a method of propulsion...but rather to Warp or Fold Space/Time.

Split Infinity

 

I think one of several problems we have is you keep talking in reference to absolute speeds. I understand that you are using the starting point as a reference, but to the ship itself, it is its own reference. All other speeds are as from measured to itself.

There are no limits with continuous acceleration. I suspect you are talking amount of time it would take to reach a given speed, but if the acceleration is continuous, then it will reach it within the ships lifetime, as it will not have the same time flow as the rest of the universe. You speak of an upper limit, what do you think sets this upper limit? There are no laws governing this, just duration.

 

I think one of several problems we have is you keep talking in reference to absolute speeds. I understand that you are using the starting point as a reference, but to the ship itself, it is its own reference. All other speeds are as from measured to itself.

There are no limits with continuous acceleration. I suspect you are talking amount of time it would take to reach a given speed, but if the acceleration is continuous, then it will reach it within the ships lifetime, as it will not have the same time flow as the rest of the universe. You speak of an upper limit, what do you think sets this upper limit? There are no laws governing this, just duration.

Bill...you touched upon a Great Question and exercise in Logic.

Since Relativistic Effects would...if an 3rd observer could observe both craft from say a Planet...would make the 2 crafts seem as if they were not moving at all as Linear Time passage upon the Planets surface would be allowing many years to pass before such a 3rd observer could notice a significant amount of distance covered by both ships...THIS ISSUE PRESENTS THIS QUESTION AND EXERCISE IN LOGIC....

...Since the passage of Linear Time observed by the Astronauts upon both ships will be perceived in the same fashion as those upon the Planet...and since if say both craft were 1.9998 Light Years away from each other and for those astronauts...1 year of Linear Time passes as using an Atomic Clock on both ships...these clocks measure 1 year of time passing...and after that year the two craft travel that distance but upon the Planet many years have passed....thus the question...since SR is the reasoning behind this Time Relativity...and since all Galaxies and the stars within and the Planets with possible life upon them are moving at such velocities....in the time it takes for the Photons to reach the Hubble Telescope...from a Galaxy 2 Billion Light Years away...as observers we are supposedly seeing Light being emitted from this Galaxy 2 Billion Years Ago...but since that Galaxy and all within it are moving at Relativistic Speeds...is it possible that any life that is sentient upon a Planet in that Galaxy living at the time that the Light was emitted 2 Billion Years ago....STILL ALIVE...even if it only had a 100 Earth Year Life Span?

The Exercise in LOGIC is...what applies and are associations that are intrinsic to the reality and condition of both the 2 Space Craft traveling at .9999c to the Planet and Alien upon it in a Galaxy which emitted light 2 Billion Years ago?

Split Infinity

 

I think one of several problems we have is you keep talking in reference to absolute speeds. I understand that you are using the starting point as a reference, but to the ship itself, it is its own reference. All other speeds are as from measured to itself.

There are no limits with continuous acceleration. I suspect you are talking amount of time it would take to reach a given speed, but if the acceleration is continuous, then it will reach it within the ships lifetime, as it will not have the same time flow as the rest of the universe. You speak of an upper limit, what do you think sets this upper limit? There are no laws governing this, just duration.

Bill...the thing is that it is IMPOSSIBLE for any form of PROPULSION to create a continuous state of acceleration. This is what I was referring to with the Jet Engine Analogy.

The Physics show us that using any form of propulsion will have an acceleration curve that can sweep up relatively quickly or be for some great lengths of time constant...but acceleration cannot remain as a constant.

Eventually...anything using propulsion will have an acceleration curve that bottoms out.

Split Infinity

 

You guys keep at it.

I think I saw it move.

 

Actually, you are wrong on this one, by quite a bit. Again, there are no scientific reasons limiting continuous acceleration, except logistics (ie, fuel). To the ship it will be 1G throughout, while to the starting point time will start slowing down for the ship quite a bit. Again, duration and time slippage. If the universe has a end then maybe there is an end point, but the book is still open on that one.

Physics show that acceleration can be a constant, to the ship again. You make outrageous claims, with no proof or sources. You logic is flawed in a major way.

Math is your friend on this one, or maybe not. It is the time dilation that limits the ship to under the speed of light, but within the ship itself everything seems normal. There is no limit on time slippage either, to the ship a second can have passed while a billion years have passed from the starting point. It goes back to basic relativity (relative to the ship), and this is a single body problem.

I suspect in my 40+ years of science interest I have put a heck of a lot more thought into this than you. You are making basic assumptions, and stating them as facts. This is very old science, it was around when I was born, and has not changed. The proofs keep coming in, the basics are correct, while some of the fine details can be jiggled.

 

Not sure where you are getting your 0.1G and 0.01G from. I'm comfortably sitting at 1G right now and so far have been at an average of 1G for my whole life without any unexpected side effects. Of course if I carry on for another 50 years or so I will probably be dead.

 

Most likely long duration drives will be very low acceleration, such as the 0.001g region. It would be nice if it were other, only time and technology will tell.

 

If a Human Body takes acceleration that produces G-Forces of .1 G every second in a LINEAR FASHION...as there is Angular and other geometric G-Force effects upon the Human Body...but if so Linear...after a minute or so a person will have Blood Flow issues that will effect vision, hearing, heart rate...YOU NAME IT! And that is just at an acceleration producing .1 G's every second.

To accelerate safely over a vast period of time to allow people on such craft to not have Physiological Medical problems...ie...DEATH...such a craft would have to accelerate at .01 G's every second.

Do the MATH...at this rate it will take...FOREVER.

Split Infinity

I'm not going to even try to ask you to back up yet another of your absurd assertions. You've obviously been sitting in a 1G field for far too long.

 

I'm not going to even try to ask you to back up yet another of your absurd assertions. You've obviously been sitting in a 1G field for far too long.

I'm not going to even try to ask you to back up yet another of your absurd assertions. You've obviously been sitting in a 1G field for far too long.

The Human Body will degenerate in many ways most in relation to Blood Circulation if a person was in a Space Craft that exceeded .01 G-Force as a CONSTANT.

Just because you are standing or sitting and experiencing 1-G has absolutely nothing to do with a Human Body experiencing LINEAR ACCELERATION that creates a greater than a .01 G constant acceleration.

G-Force constants of just .02-G will create major medical problems and even DEATH if .02-G remains a constant for any multiple day period of time. This is just accelerating at a velocity at which .02-G will remain constant...never mind the Full...1.0-G you are referring to...in a manner that has nothing to do with this issue or problem.

Do yourself a favor and try not to be so quick to JUMP ON ANY POSSIBILITY OF A MISTAKE...that you think I might have made...as you have obviously done here.

You didn't even understand the issue as your reply demonstrates and rather than voice either your objections or support for the post...you decided to reply IN A NEGATIVE MANNER...that was targeted at the person who posted...ie...ME...as you were licking your chops thinking to yourself..."AH HA! Split Infinity has made a MISTAKE and this is my chance to show the Membership what a FOOL Split Infinity is!...AAAAHA HA HA!!!"

Because you were so intently concentrating upon finding any possible flaw or error in one of my posts...you did not even realize the incredible stupidity that allowed you to reply and site reasoning that not only has nothing to do with what was being discussed...but also allows every member here to see just what your true intent was in replying in such a manner.

The only ABSURD ASSERTIONS being raised here are those that you have leveled against my post as well as your making yourself look...petty and unable to come to terms with some emotional issues you obviously have that pertain to vindictiveness and child like revenge upon a person who would never have the problems you are having with the kind and size of the baggage you are carrying around with you.

Do yourself a favor and drop that baggage. All it will do is hurt you.

Split Infinity

 

Actually, you are wrong on this one, by quite a bit. Again, there are no scientific reasons limiting continuous acceleration, except logistics (ie, fuel). To the ship it will be 1G throughout, while to the starting point time will start slowing down for the ship quite a bit. Again, duration and time slippage. If the universe has a end then maybe there is an end point, but the book is still open on that one.

Physics show that acceleration can be a constant, to the ship again. You make outrageous claims, with no proof or sources. You logic is flawed in a major way.

Math is your friend on this one, or maybe not. It is the time dilation that limits the ship to under the speed of light, but within the ship itself everything seems normal. There is no limit on time slippage either, to the ship a second can have passed while a billion years have passed from the starting point. It goes back to basic relativity (relative to the ship), and this is a single body problem.

I suspect in my 40+ years of science interest I have put a heck of a lot more thought into this than you. You are making basic assumptions, and stating them as facts. This is very old science, it was around when I was born, and has not changed. The proofs keep coming in, the basics are correct, while some of the fine details can be jiggled.

Bill...now YOU are making an assumption. I agree that acceleration can be at constant...but even if say the Universe will exist FOREVER...and let's say the craft is SAFELY accelerated at .01-G...by a FORM OF PROPULSION...it could never achieve or exceed the Speed of Light thus at the point that such a craft reached a certain velocity WHICH WOULD BE UNDER...C...acceleration would cease and no longer be constant.

You can't have it both way's. You can't have C as the maximum Universal Speed Limit as well as a Crafts Acceleration be FOREVER CONSTANT.

Also the other point I brought up...and method or form of Propulsion by it's very nature of what is happening...why it is happening...what maximum velocity such a propulsion system could achieve...are ALL QUESTIONS THAT HAVE ANSWERS THAT DO NOT INCLUDE...By a constant acceleration a velocity driven and achieved by a form of propulsion was obtained at and beyond the velocity of C.

My original post relating to this stated that at a distance of 1 Billion Light Years apart...two space craft being accelerated SAFELY AS TO NOT KILL THE PASSENGERS...would take forever and a day to get up to .9999c...never mind traveling the 1 Billion Light Years.

I STAND BY MY POST. And you have not presented anything to disprove it.

Split Infinity...p.s....NEVER assume your 40 plus years of Science Interests make your created logic and proofs any more viable than another just because you believe you have the only valid avenue of thought upon a matter.

Very often such assumptions...well...you know.