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Everything posted by imatfaal
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What difference does it make if the Schwarzschild radii touch?
imatfaal replied to Robittybob1's topic in Relativity
[tongue in check & devil's advocate] Weellll... before it goes into the black hole there is an entropy involved in this matter which makes up the mass and after it goes through the event horizon it might seem that this information is lost. However this information is stored in the surface of the event horizon - thus the entropy of the black hole is related to the surface area of the black hole. If you really want to crunch the numbers there are 3.838e69 planck areas per metre; and the entropy is proportional to a quarter of the surface area of the event horizon. The logarithm of the number of microstates (which is the entropy) of the material which took information into the black must therefore also be proportional to the surface area of the event horizon - this would be very closely related to the mass of the material which went in [\tongue in check & devil's advocate] -
We have a theorem in computational quantum mechanics called the no cloning theorem which states that it is not possible to create a perfect copy of a particle in an unknown and arbitrary state; this can be proved at the level of one or two qubits in highly simplified relationships so I see not a lot of reasons why it would not apply at a macro-level which is just a lot of microlevels and which is not constrained to simple relationships. Of course some might say that we could (in some future technology) measure every particle to remove the unknown element - but on these levels measurement is enough to collapse systems and change settings; and I wouldn't want to be doing that to my head
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What difference does it make if the Schwarzschild radii touch?
imatfaal replied to Robittybob1's topic in Relativity
Mordred - surely in terms of the s'child radius you must be able to consider the black hole without considering ANY content outside - the schwartzchild radius is the product of the vacuum solution to the field equations for a non-rotating non-charged black hole; with my emphasis being on a vacuum solution. You also get a solution to the field equations which gives a hawking-penrose spacelike singularity at the centre of a black hole. I realise that this work causes more problems that it answers in that no one really believes this is a correct model of reality - but it is GR and the best we have at present; it might have shown where we need an alternative to GR but I didn't think we had one yet I do not see how these two sets of solutions are compatible with your assertions that you cannot look at black holes in isolation and that mass / gravity is a shell at the EH -
This is the line I do not understand / agree with - and I got no further "An indexed force magnitude (Fnx) may be written as; Fnx = (mnvx2)2/ħc" When I use vector notation for Forces and end up with a expression such as F12 it means the Force exerted on object two by object one; the most obvious example is Force due to Gravitation: [latex] \mathbf{F}_{12}=-\frac{G m_1 m_2}{\left |\mathbf{r}_{12} \right |^2} \cdot \hat{r}_{12} [/latex] The force on 2 due to 1 - and this makes it clear why gravitational force is shown as a negative as well; for the vectors to match then the force must be negative in order to be attractive I would read Fnx as the force on x due to n - you could then not split this up to getting the velocity from one object and the mass from a second. Now it is clear you are using hte term in a different way - unfortunely I do not understand this way
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To be honest iNow you would struggle to find any large and representative group that did not split on broadly similar terms (I mean in reference to the benefit/cost of leaving) - however the overall question remains balanced. Similar to your situation in the republican primaries in which rationality and pragmatism seem to be taking a back seat to bigotry and popularism we have a scenario in which almost every interest group / business confederation / mainstream political party thinks that exit will be harmful in both short and long term - yet the plebiscite is balanced and one small incident at the time of the referendum could be enough to sway opinion towards exit.
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A cement mixer collided with a prison van on the Kingston by-pass. Motorists are asked to be on the look-out for 16 hardened criminals.
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A cement mixer collided with a prison van on the Kingston by-pass. Motorists are asked to be on the look-out for 16 hardened criminals.
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Low Energy Nuclear Reactions / Cold Fusion (thread split)
imatfaal replied to barfbag's topic in Speculations
Haram I won't quote your message otherwise it will all get very long. Why were the scientists stigmatized? To an extent the ostracisation is exaggerated and to a further extent it is deserved; their experiment was flawed (that happens to everyone), they made mistakes (again everyone), they were too excited and lost focus (again), and they stopped being disinterested in the result (again). But when great research teams around the world explained the problems, showed there was not independent corroboration, detailed their misgivings in the methodology, failed to reproduce when doing things right, and asked for a re-think - the original teams doubled down and refused to admit that they had cocked up. For a better example of how they should have behaved look at the history of the superluminal neutrinos at gran sasso -
The section starting "A Scalar definition...." is a bit like the cartoon "and then a miracle occurs". You cannot just ignore the fact that you have equated a force with a manipulated energy and suddenly claim that the LHS of the equation is equal to a dimensionless unit (or simple number as you have done). A simple dimensional analysis shows your initial assertion is incorrect Energy => L2 M T-2 Your formulation is Energy is => Sqrt ( [L2 M T-1] [L T-1] ) Sqrt (L3 M T-2) L3/2 M1/2 T-1
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Remember your weight is on the axle so it is kinda held in place - but it should not be too tight nor too loose; too loose is probably worse. You should not fight to close the QR lever - but nor should you be able to turn the axle on its axis by turning the QR lever. If String has disc brakes it would be better to be a little on the tight side (disc brakes apply force/torque on only one side of the fork and therefore there is a torque around the axis of the steerer tube) - rim brakes (which would make sense as he posted a picture of some nasty Clarks brake pads last week ) produce no torque in that axis as the retarding torque/force is applied on both sides of the wheel equally. You can test by holding brakes on and pushing the bike forward and pull backwards against the front wheel braking - there should be no movement whatsoever of the axle in any direction. Shimano recommend that there should be some axial play in the wheel on the axle before attachment to forks - but that the action of the QR clamping down should bend the axle enough to take up the play. But crucially you should not get an increase in the friction on the wheel when you clamp it in; ie it should spin as freely when in your hand as when clamped into the forks - this is why you need the play beforehand. String - if you are gonna be doing any maintenance (and forgive me if you already know all this) check out Park Tools website for their huge array of tips and advice / Sheldon Browns Website / andor By Zinn and the Art of Bicycle Maintenance
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An unappealing Bond perhaps - but a perfect fit for the character from the books. And the only one till Daniel Craig that actually looked like a (wrong side of) borderline psychopath.
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Why would a supernatural being be hampered by our logical systems and our human inadequacies - just because we imagine things impossible that really does not mean that they must be impossible? This is a silly argument against the supernatural - which by definition is outside the scope of our science and rationalism; "I don't believe in something which transcends human understanding and knowledge because a quintessentially human rational logical argument denies the possibility of it". I don't believe in god because I have seen no evidence whatsoever for her existence. This situation is made worse by my well-evidenced distrust of many of those who claim to have evidence of her existence.
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Yes - I missed that. The oscillation are so pronounced on my good bike as to be slightly unbelievable - and the only difference between that and the commuter is the quality of the bearings. It is also disconcerting that the valve - which looks as if it should end up at the bottom ends up half way up one side. New bearings can take a while to fully loosen up - when assembled they should be packed with grease and take a while to get into full rolling mode. The other possibility is that the Quick release bolt is too tight and is bending the axle slightly and causing the bearings to rub I presume the BBC has sold call the midwife to the USA networks?
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I have just done ten trial spins on my front wheel and it does not recoil in any way. This leads me to think one of a few things maybe true: 1. Stringjunky is a dangerous sociopath trying to warp our minds with crazy ideas 2. My old and knackered bearings are not doing the same sort of thing 3. The fact that my bike is suspended absolutely steadily in a workstand removes all other forms of movement which might cloud the experiment and produce false positive results My favourite is number three Merged post follows: [/mp] Am now trying to refute 2 by testing my road bike with uber-posh ceramic bearings rather than my sketchy old commute with pepper-grinder smooth steel cup and cone bearings Merged post follows: Completely different result. Commuter bike stopped dead and had no oscillation whatsoever Road bike oscillated hugely - 22 movements (11 cycles) first trial ending with the valve at just before 3 o'clock and the seam (where the strip of metal which is bent into the a circle to make the rim) is welded at just before 9 o'clock. [mp] 14 oscillations (7 cycles) with final position indistinguishable from trial one Conclusion - it is an oscillation on Stringjunky's bike settling to a equilibrium position; however the state of his bearings are such that it is more than critically damped and only does 1/2 a cycle. I think you may need new bearings - I am certain that I do on my Commuter.
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Low Energy Nuclear Reactions / Cold Fusion (thread split)
imatfaal replied to barfbag's topic in Speculations
The easy thing is with energy production is that when "Galileos" cry that they are being ignored by the establishment there is one easy response; if you are generating power for less than you are putting in then you can start to sell it back to the national grid. This would soon get academics attention - but none of them actually manage this overunity production in anything apart from stage managed and clearly fallacious show-trials. It is a not a difficult experiment that needs highly trained observers - just an isolated box that takes in X watts and exports X+E watts. Maybe I should recheck my sums - but a back of the envelope calculation shows that we would need about .1% of the area of the uk covered in Solar Cells that were 100% efficient to cover our Electricity needs here - and about 5 times that amount for total household energy consumption. Not at the present feasible for a cloudy country at 51 degrees north. Note hydrogen based is not renewable - it is just a clean fuel but the energy to create hydrogen still needs to come from somewhere. And - no need to apologise for your English it is superb and I hadn't even thought that you were not a native speaker -
What is the best 3D description of Gravitational waves?
imatfaal replied to Robittybob1's topic in Speculations
Rob this is why these discussions are so frustrating. You are talking about your speculation being unchallenged in one thread - yet it becomes clear that you do not understand that cos or sine of anything can only vary between 1 and minus 1. This is like saying you should be playing for the NZ 2020 team in the Semi-final and then asking what this heavy lump of willow actually does. so to answer your questions [latex]\cos \theta[/latex] max value is 1 min value is minus 1. [latex]\sin \left[2\omega(t-R/c)\right][/latex] max value is 1 min value is minus 1 obviously the max and min value of their product is the same. I thought I had made it abundantly clear in my previous post that the [latex]\cos \theta[/latex] section deals with the change in the Amplitude of the certain polarisation with the change in the angle from the perpendicular whilst the [latex]\sin \left[2\omega(t-R/c)\right][/latex] section deals with the evolution of the function over time. You were claiming you did not see how such a small change in t could make any difference to the overall function - I hoped that the graph on wolfram alpha would show you that this formulation was the basis of a wave equation and in fact was very important in determining the sort of signal we expect You know what theta is and you know you are taking either the sine or the 1+cos2 so you know the value of the expression which deals with the change in Amplitude due to angle of observation. Take this into account - or have you already. -
! Moderator Note PoPpAScience Even though I am sure you will interpret this as yet another dogmatic and oppressive post from an authoritarian atheist - Please take note of the following requests: 1. Stop reporting posts that you merely disagree with. The staff do not have unlimited time and we are all volunteers - we really do not want to start the day with a bag-full of spurious claims of rule breaches. 2. Perhaps take a bit more time to read the posts before responding to them - your claims of irrationality and bigotry based on the responses in this thread from the membership are quite frankly ludicrous. Either you are trolling and thus responding merely to annoy, or you are preaching thus not reading the messages sent to you and just providing pat replies - neither is acceptable. 3. If you continue to describe the membership in general or any members in particular as bad, idiotic, or any other insulting terms you will be suspended. 4. When asked direct questions concerning factual assertions you have made it is necessary for you to reply Re-read the rules with regard to yourself - Matthew 7:5 - before reporting anything and before continuing with this current thread. And do NOT respond to this moderation within the thread - responses will be summarily removed; report this post if you feel you have a genuine grievance
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Female vs Male OSF users...I'm disappointed.
imatfaal replied to Elite Engineer's topic in The Lounge
! Moderator Note I think with that excellent post immediately above, which in and of itself refutes the OP, and which expresses the views of many of our members in no uncertain terms it might be time to close this thread. Elite Engineer - please refrain from making threads to discuss an individual member even if you do not name them; it is rude, inconsiderate, and in this case insulting and thus against the rules. I think you will also find that many new members who seem to be approaching the forum in an open, friendly manner through well-written and thoughtful posts will receive a huge amount of up-votes. Personally I will up-vote a new member far more frequently than I would an old-stager. -
What is the best 3D description of Gravitational waves?
imatfaal replied to Robittybob1's topic in Speculations
4e16=4.0E+16=4*1016 h_plus is cos and h_cross is sin cos and sine will be at a different phase from each other - so for the same t you will get different amounts of h_plus and h_cross -
Superconductivity Experimentation
imatfaal replied to gmelancon's topic in Modern and Theoretical Physics
Not really no. They are both saying quite politely that the evidence provided is sorely lacking and that testing transitions is all very well but superconductors have two stand out and very testable properties - no resistance and the expulsion of the magnetic field; both posts suggest that some evidence of this, which would be obtainable if (and it is a big if) the substance is superconducting, is completely essential to any claim. -
What is the best 3D description of Gravitational waves?
imatfaal replied to Robittybob1's topic in Speculations
t is the variable of the equation - it runs from one figure to another continuously - for each t there is one and only one h_cross and h_plus. And yes I used 100km just to put a number in there -
What is the best 3D description of Gravitational waves?
imatfaal replied to Robittybob1's topic in Speculations
Rob 1.That last section of the equation gives you a nice oscillation (it is a pretty standard expression in waves) this is what it looks like http://www.wolframalpha.com/input/?i=cos%5B2*(sqrt((6.67e-11)*(1.3e32)%2F(100000%5E3)))(t-4e16)%5D [latex] \cos\left[2\omega(t - R/c)\right] [/latex] Bear in mind - It is a cos or sin function so the answer will be between -1 and 1 whatever the inputs 2. This bit deals with the inclination above the orbital plane - actually the angle between the perpendicular (ie angular momentum direction) and the viewer [latex] (1+\cos^2\theta) [/latex] 3. This is to do the overall strength [latex] \frac{G^2}{c^4}\, \frac{2 m_1 m_2}{r} [/latex] 4. And this is the fall off with distance [latex] -\frac{1}{R}[/latex] - you see it is one over distance not the one of distance squared of gravitation attraction [mp][/mp] You can also see that at no point in the equations is there a [latex]\phi[/latex] (with all due respect to our Chief Executive Offworlder) - so there is no variance in the amplitude in the plane of the orbit ( if we assume [latex]\theta[/latex] the polar does "latitude" and [latex]\phi[/latex] the azimuthal does "longitude"). You would need avariation in both [latex]\theta[/latex] and [latex]\phi[/latex] for a spiral -
How You'd Actually Put General Relativity to the Test
imatfaal replied to metacogitans's topic in Speculations
! Moderator Note No theory and no model - and now with added conspiracy; sorry but this is not what the speculations forum is for. I am pretty sure I asked you to read the rules of this forum in the modnote under which the thread was moved - you have failed to comply to any extent. Thread Locked. -
Just as a theoretical question - why not? This site - like many science sites on the internet - could exist solely to educate and explain; ie everything written would either be a question or established physics. We decided to indulge those who wish to have their own notions tested in a scientific arena - but we set very strict rules. We are fairly confident that any new and important idea is both very unlikely and will be spotted within seconds by the university level teachers who roam these halls. Your speculations are a case in point - they are so poorly founded that it is soon obvious that any correct ideas are more by luck than by good judgment. They do not have good grounding in science - we take small steps from the known to the unknown; whereas your speculations are based on misunderstandings or popularisations.