Sunday, October 12, 2014

How To Ask An Ignorant Astrophysics Question

Being a volunteer on All Experts affords one the opportunity to extend his or her teaching, even if now retired from formal university teaching. Also, it offers the ability to interact with many young and curious minds, all seeking to better understand the universe in which we live.  The problem is when one encounters minds led astray by pseudo-scientific bafflegab and pseudo-mathematical twaddle  (warned about by Charles Seife in his book, Proofiness: How You're Being Fooled by the Numbers. )

Anyway, my encounter with this sort of bollocks started yesterday with an apparently innocent hypothetical question, by a Canadian student named "Diana":

QUESTION: If a bullet traveling beside the ISS was to gradually increase in mass (while continuing at the exact same velocity) it would slowly descend towards the earth as it orbits.

Now it is 30 m above the earth traveling at the same velocity as the ISS.  If its mass now remained constant and its velocity begins to increase, it will slowly rise upwards towards space while continuing to orbit.

 Can we say that it moves upward not only do to its centripetal force, but also due to an increased density of the space surrounding it ?


Note this is the extent of the question, and there is no elaboration specifically of the last portion referencing the density of the space "surrounding it".


My reply was as follows:

A typical bullet has a standard mass of 100 g (0.1 kg). This is roughly the same as about 45% of meteoritic debris. Hence, at the velocity you are proposing (same as ISS) it would behave like meteoritic debris and be burned up in the Earth's atmosphere on entering -  before it could ever get as low as 30 m, even if its mass increased (refer to the Chelyabinsk object which burned up in February last year over Russia).
 Hence, there is no chance of it's "moving upward".

 This elicited the further reply, if you can believe it:

QUESTION: Hypothetically if there was no atmosphere around the earth.

Note here the positing of an absurd hypothetical - an airless Earth. Of course, then it ceases to be Earth. As I further noted in my response (clearly invoking way too much common sense):

How could an airless world have occupants that launched an ISS? Also your hypothetical is contradicted by  referring to "increased density of the space surrounding it".  Which, unless I've missed your meaning, has to refer to atmosphere. I mean, from where else would this increased density come?
In any case, even with the extremely implausible conditions you suggest, it is impossible that the bullet would "rise up" because - after increasing its mass (again, as you suggest) the increased gravitational pull of Earth (F ~ GMm/r2)  would have ensured an ultimately decayed orbit and impact. Not "rising up".

 Addendum: At a height of 30 m from 'Earth' the velocity of the bullet would have had to increase to 3.66 x 10 6 m/s to sustain any orbit - far less move up- which is preposterous, given the ISS velocity is only 7.71 x 103 m/s.   It is all very well to propose "hypotheticals" but we must expect some touchstone in reality, physical laws. (I.e. where will the energy come from to countermand the force of Earth's gravitational attraction?)

 This finally exposed her real shtick with the elaboration of a nonsense source of "density" to allow the bullet to have a magical trajectory:

You're hilarious !
> How could an airless world have occupants that launched an ISS?
That's exactly why we use the word hypothetical.
> would have ensured an ultimately decayed orbit and impact.
No the velocity was kept constant and only enough mass was added to bring it close to the earth.
Because space is not empty but made of quantum particles of mass we believe the increased velocity would indeed cause a higher density thus pushing the bullet upwards. See:

Where do these ridiculous websites emanate from that enable young minds to be hooked by bollocks? Quantum particles of mass - sufficient to affect a bullet?  As I wrote back to her, also clarifying the applicability of the term "hypothetical":
This is why I reject most hypothetical questions unless they at least assume a relative basis in reality (i.e. if you are writing or talking about a problem relative to *Earth*, then we assume Earth parameters ab initio.  Thus, in my frame of reference, "hypothetical" has limits. If you choose the Earth as the planet you're examining in a given problem context, then it has the density, mass, temperature profile etc. and YES ...atmosphere of Earth. If not,  you choose a planet example that fits the conditions you require or imagine a completely hypothetical example planet - not Earth!
 Re: Space not being empty, sure ok, but "quantum particles of mass" would not have had any effect on macroscopic mass, e.g. a bullet.  See, for example, David Bohm's treatment in his book Wholeness and the Implicate Order.  Bohm notes 1 cc of empty space has a mass-energy that surpasses that of the known matter universe, but it can't be used to move or affect a macroscopic material particle.

 The latter point is critical. Also emphasized in the paper 'Does Physics Legislate Cosmogony?' by John Wheeler and C.M. Patton. In the paper they calculate (or estimate, more accurately) the effective mass-density of quantum vacuum fluctuations by using:

 = [ ( h c/ L2) c ] / L 3

where L is the Planck length, or  10 -33  cm. This result becomes 10 94  g/ cm3. But again, the problem is that the immense density isn't available to do anything to macroscopic objects, like bullets.  In order to affect bullets, they'd have to be the same scale as the Planck length, but they are not.

And this elicited the barrage of bunkum and proofiness - now delivered by "Jeanine" - supposedly the alter persona of "Diana". (Hmm... never realized multiple personality disorder was so prevalent there).  She wrote:

How on earth can you possibly call this crap?
Earth's orbit Velocity and Circumference must be calculated via "pure mathematics" in accordance with the Speed of Light. 

When this is done, the true reality of our galaxy is easily understood.

Hence (according to the SOLARMath® TABLE below) when the correct orbit velocity of earth (30,689.1802376259 m/s) is calculated according to Einstein's "c", the  following  list  of  extraordinary  mathematics  unfolds.  And please do not jump to immature refutes by stating that the UNITS do not work.  ALL units work perfectly - Link

1)     Speed of Light  =  orbit Velocity^2  /  Pi       (Enormously Important Equation)

2)     Speed of Light  =  Acceleration of Gravity  x  orbit Time

3)     Speed of Light  =  Acceleration of Gravity  x  (earth Volume  /  orbit Circumference x Tau2)

4)     Speed of Light  =  Acceleration of planet earth in orbit  x  Diameter of orbit

5)     Speed of Light  =  Density of earth  x  orbit Velocity x 2

(And a string of 5 more proofy math relations that make no sense)

Here is where the baloney alarm went into overdrive and I knew this girl (or girls) had been sucker-punched by nonsense.

In full display we behold the “proofiness” that Charles Seife referenced in his book, Proofiness: How You're Being Fooled by the NumbersSeife decried the tactic of using numbers not just to lie but to baffle the susceptible and gullible with bullshit.  He refers to a common failing of most people unversed in math to be hoodwinked merely because some form of math or numbers are interjected into arguments.  Not just using numbers to bolster one's argument. In his words, to use fake numbers to prove falsehoods and to seek to prove something is true - even when it's not- is one of the most egregious forms of  intellectual  fraud.  The first thing any first year Physics student learns - or should - is to check for consistency of the physical units used. If their combination doesn't yield any recognized physical quantity - defined as part of the standards and constants published yearly by the American Institute of Physics - then the results are balderdash, pure and simple. Let's take her example (4) where:

Speed of Light  =  Acceleration of planet earth in orbit  x  Diameter of orbit

What are the units here? The speed of light c is in meters per second, or m/s. The acceleration a is given in terms of  m/ s 2  and the diameter of any orbit (any orbit) is a length so in meters (m). Then multiplying them together one gets:

(m/s)  =  ?  (m/ s 2) (m)  =  m2 / s 2

Which is emphatically not the same as the units for velocity of light! Let's also check her "enormously important equation" (1): Speed of Light  =  orbit Velocity^2  /  Pi      

Again, we examine the product of the units to see if there's a quantity that results that makes any sense or if this girl is just seeing things, or seeing what she wants to see.  We have the speed of light on one side (units m/s ) and on the other the orbit velocity squared:

(m/s)2    =  m2 / s 2

Note that the presence of pi is neither here nor there as it's a dimensionless mathematical constant.

The thing that really bothered me in all this, not so much the snarkiness and bogus certitude of these young women, was their failure to recognize that the combination of units yields zilch. A squared velocity is simply NOT the same as a velocity. Both girls - if indeed there are two - would merit an F in any physics class of mine.  Worse, if I could I'd deliver an F-minus because of the lack of critical thinking.

Sadly, if this girl or girls are infected by this stupidity many others might be too. Who knows how many physics students have gone on to the website referenced and then belabored their profs with this bullshit, wasting all kinds of time?  But one thing I've learned is you can't argue with ignorant students or ignorant people who are already committed to believe what they want. In this case, because the "maths' seems to work out (at least in their heads) they believe it like a sacred book.

One more confirmation of  Charles Seife's thesis in his book, Proofiness: How You're Being Fooled by the Numbers, that too many of us are too often mesmerized by fake quantities and made to look like ignorant fools because of it.

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