It's always welcome when newbies express their personal thoughts and speculations regarding the cosmos, but they need to keep in mind: a) their level of knowledge compared to others who've put in many more hours or YEARS, and b) that if and when they attack astronomers and physicists in whatever way, they leave themselves open for takedowns. Such is the case with a recent article in the Intertel Journal Integra - by Chester B. Smith entitled 'Thoughts concerning the Universe'.
I could skewer all of Mr. Smith’s pet fantasies about how he perceives the universe, but just want to examine more closely a few where he oversteps the bounds of scholarly proprietary by taking pot shots at physicists’ logical or thinking capacities.
In his first paragraph, for example he wonders if physicists “share a common hallucinatory drug” in respect of how they ascertain the age of the universe by measuring its red shift. Like many neophytes, he conflates the distance determinations with ages, say of galaxies, and hence wonders “how a distant galaxy was formed at the beginning of the universe rather than 6 billion years later”.
However, pure distances alone don’t translate into ages. One must be aware of parameters beyond that. The most critical of these is the Hubble constant. One can think of it as setting the “’slope” or gradient for the relationship that links the velocity of recession of a cosmological object to its distance. Hence, it is more fundamental than just the single distance to a given object – since the cosmos is expanding in all directions and there is no one defined center of origin! (I.e. we cannot geometrically pinpoint the location of the Big Bang because it was an instantaneous inflation of both space and time)
Then, the age of the universe (in seconds) is: t = 1/ H_o
I could skewer all of Mr. Smith’s pet fantasies about how he perceives the universe, but just want to examine more closely a few where he oversteps the bounds of scholarly proprietary by taking pot shots at physicists’ logical or thinking capacities.
In his first paragraph, for example he wonders if physicists “share a common hallucinatory drug” in respect of how they ascertain the age of the universe by measuring its red shift. Like many neophytes, he conflates the distance determinations with ages, say of galaxies, and hence wonders “how a distant galaxy was formed at the beginning of the universe rather than 6 billion years later”.
However, pure distances alone don’t translate into ages. One must be aware of parameters beyond that. The most critical of these is the Hubble constant. One can think of it as setting the “’slope” or gradient for the relationship that links the velocity of recession of a cosmological object to its distance. Hence, it is more fundamental than just the single distance to a given object – since the cosmos is expanding in all directions and there is no one defined center of origin! (I.e. we cannot geometrically pinpoint the location of the Big Bang because it was an instantaneous inflation of both space and time)
Then, the age of the universe (in seconds) is: t = 1/ H_o
where H_o is the Hubble constant.
The beauty of this computation is that it renders redundant all distractive issues and questions such as "what distances are we rewinding back to", which truly aren't much use! Currently, we estimate H _o~ 70 km/ sec/Mpc, where Mpc denotes ‘megaparsec’ – and each parsec has 3.26 light years.
The above is little use, however, without changing a lot of units and ensuring their consistency. The key initial step is to obtain the megaparsec equivalent for kilometers:
MPC(km) = (c) (86400)(365.25)(3.26)x 10^6
where c = 300,000 km/sec, the velocity of light
Then: MPC(km) = 3.08 x 10^19 km/Mpc
Now, what is usually colloquially called the "Hubble constant" is in reality the Hubble scale factor (a = 70 km/ sec/Mpc). The REAL Hubble constant (H_o) is the scale factor divided by MPC(km):
H_o = a/ MPC(km) = 2.26 x 10^-18 s^-1
then, t_o = 1/ H_o = 1/ {2.26 x 10^-18 /s} = 4.4 x 10^17 s
Which, when converted, is about 1.3 x 10^10 yrs. or 13 billion years in age.
Smith’s next point of bafflement concerns gravity and “how it could change in a star unless it’s imposed from outside”.
But think of a star like a gigantic onion with multiple layers. The layers at the top or near the surface are lighter, because they have lighter gases which aren’t so compressed. But as one piles additional layer upon layer the weight of those layers presses down more on the layers toward the center of the star. Thus, the gravity is greatest near the stellar core and this helps to compress the gases in the core to their maximum pressure. Hence, it is precisely within the star’s core we expect the nuclear fusion reactions which provide its energy to occur.
A star, Main sequence – like the Sun – remains in balance and stability (what we call “hydrostatic equilibrium”) because each layer’s weight acting downwards is balanced by the radiation pressure (from the outward flowing radiation) acting outwards. I believe this is what Smith means when he argues against stars “balancing themselves against themselves”. Except they don’t: two distinct forces are balanced at each layer against each other.
Smith also appears to have problems grasping how “space dust” can agglomerate into a stable mass and then “combust” as a new star. Perhaps one of the best books he could get (as well as anyone else mystified by the process) is Isaac Asimov’s ‘The Collapsing Universe’. Using basic physics principles Asimov shows (Chapter 3, ‘Compressed Matter: Stars’ p. 55) exactly how the accumulation of dust and gas unfold – under the influence of gravitational attraction – for form a new star.
Another paragraph of mystification becomes clear once basic principles are learned:
Smith writes:
“I believe the purpose for the change from pure energy into the various forms of matter is to achieve balancing or stabilization in order to prevent collapse back to the original point”. But pure energy isn’t needed for this. . We know that the cosmological density parameter is crucial, viz.
OMEGA = rho / rho_ c
where rho is the observed cosmic density, and rho_ c is some critical value or threshold such that only if:
rho > rho_ c
the cosmic density reverses the expansion and forces a new cycle, starting with Big Bang. But current data, e.g. from Boomerang and other satellite detectors (See, e.g. 'Supernovae, Dark Energy and the Accelerating Universe', by Saul Perlmutter, in Physics Today, April, 2003,) shows that W » 0.3 or that: r = 0.3 (rho_c) I.e. that rho (less than) rho_c so there is no danger of the cosmos decelerating, and hence re-collapse. Hence, it is the residual mass of the cosmos (mostly in dark matter, such as black holes, intergalactic matter etc,) which inhibits any collapse, not “pure energy”.
Another mystifying comment from Smith is:
“Why assume the laws of physics are abandoned once you look into outer space?”
But who says they are, other than Smith? In fact, the laws of physics attain their state of maximal potency and application in space, and again – we have measurements to back up whatever claims are made. There is no “mystery” other than one deliberately confecting such, as Smith does. For example, he appears to question the rational basis of the Big Bang, and yet we have the evidence for the isotropic 2.7 K relic radiation – first observed by Penzias and Wilson at Bell Labs in 1965 and for which they won a Nobel Prize twenty-odd years later – which shows a cosmic fireball had to have originated some 13 billion years ago. That he (or others) may not be able to wrap their brains around that doesn’t make it less so, or counterfactual.
Like many other hobby- hunchers I see (those who come up with oddball conjectures to try to supplant accepted physics) Smith also displays an ambiguity in his terminology which conflates differing aspects of the physical world without a proper description or definition. For example, at the bottom of p. 18 he advances formation of an “energy field”. But there is no such thing. What we have are electrostatic fields, electro-magnetic fields, strong and weak nuclear fields, and gravitational fields. There is no …generic…”energy field” and none has been observed or measured. Neither is there such a thing as a “universe field” (p. 19 top). You can't simply make up entities like "fields" in your head and confer reality on them by fiat!
Smith rambles on that "we love mystery at the expense of logic” (ibid.) but this is codswallop. The thing most physicists hate above all is leaving any “mystery” out there so that assorted obscurantists, crackpots, cranks and others can parlay it into mumbo-jumbo….say like Michael Talbot’s alleged holographic “miracle” fields popularized in his Holographic Universe.
The truth is that physicists are ruthless in their logic applied to the cosmos, but this logic is always framed in its most concise and precise form – the language of mathematics. Physicists understand that without mathematics, such as tensor calculus, differential equations, non-commutative geometry and the like, we’d only really be able to theorize about one one thousandth of what we have. Mathematics makes the transfer from verbal conjecture to hypothesis to testing concrete.
Thus, it’s odd when Smith blurts that “math is likewise inefficient’. Perhaps only because he doesn’t know enough, and maybe never even took an advanced (e.g. college algebra) course, far less calculus or differential equations.
He appears to arrive at this nonsense by referring to a “pre-telescope European astronomer who proved mathematically that the sun and planets revolved around the earth..he accomplished this by adding loops in the orbits”
He is referring, of course, to the astrologer Claudius Ptolemy who generated a complex model (published in his Almagest) using “epicycles” (the added loops of which Smith writes) to explain the planetary motions, especially the retrograde motion of Mars (when it appears to be moving backward relative to the fixed stars)..
The problem, of course, is that the Ptolemaic system of epicycles is mythical and not based on the actual heliocentric system which follows from Newtonian principles of gravitation. It is here that the use of mathematics such as the differential equations of celestial mechanics, proves far more efficient and powerful than endlessly adding cycles that have no physical basis.
Thus it is that the over-complicated system of epicycles is rendered redundant once one understands and appreciates the planets move in elliptical orbits, not in circular ones. Ptolemy’s error was in trying to squeeze planetary motions into a “perfect” circular mold. Once this change to the actual physical orbits is made, then the appropriate equations, such as Kepler’s, e.g.
n(t – T) = E – e sin E
where n is the mean motion (in degrees per day or per second), t the referenced time, T the time of perihelion passage (e.g. closest point to the Sun), e is the eccentricity and E is the eccentric anomaly.
This can then be used in conjunction with others to arrive at the orbital elements for all the planets. These include: the eccentricity of the orbit, e (e.g. how elliptical it is or the deviation from circularity), the semi-major axis, a, or the mean distance to the Sun, the inclination (i) of the orbit – or the tilt of its plane with respect to the reference plane, and others.
Once these are known, I can then use the relevant equations, as I have done – whether in university projects or my own research – to accurately forecast the position of any planet well into the future – say the position of Jupiter in the sky on Feb. 1, 2100.
This is something Ptolemy and his epicycles could never do, and certainly not to the accuracy I can attain – an accuracy, by the way, that enables us to land complex Rovers on Mars, and mount close flybys of other worlds.
This alone skewers Smith’s claim that “mathematics is more of a copy machine than a discovery tool”
For his info, without the mathematics of tensors, general relativity would have remained a wild speculation and never attained theory stage. Without the basis of complex analysis neither plasma physics or quantum mechanics would have attained the maturity they have.
What Smith’s foray into the universe shows, if nothing else, is that a little knowledge is a dangerous thing – if it leads one to accept a perception of the cosmos totally fabricated from vague hunches, professed “common sense” and a mish mash of whacky ideas and terms …picked up from who knows where.
A final suggestion to Smith: there are terrific online courses in astronomy and physics available at the Yale University Open Course site:
http://oyc.yale.edu/courselist
See, e.g. the Astrophysics course at the top and Fundamentals of physics I,II lower down.
Even if you’re not mathematically adept, exposure to even some of these principles, concepts and illustrations will dispel at least some of your misconceptions about the cosmos! The question for you to address is: Do you wish to persist in these pet, subjective misconceptions ….or do you want to remove the blinders?
The beauty of this computation is that it renders redundant all distractive issues and questions such as "what distances are we rewinding back to", which truly aren't much use! Currently, we estimate H _o~ 70 km/ sec/Mpc, where Mpc denotes ‘megaparsec’ – and each parsec has 3.26 light years.
The above is little use, however, without changing a lot of units and ensuring their consistency. The key initial step is to obtain the megaparsec equivalent for kilometers:
MPC(km) = (c) (86400)(365.25)(3.26)x 10^6
where c = 300,000 km/sec, the velocity of light
Then: MPC(km) = 3.08 x 10^19 km/Mpc
Now, what is usually colloquially called the "Hubble constant" is in reality the Hubble scale factor (a = 70 km/ sec/Mpc). The REAL Hubble constant (H_o) is the scale factor divided by MPC(km):
H_o = a/ MPC(km) = 2.26 x 10^-18 s^-1
then, t_o = 1/ H_o = 1/ {2.26 x 10^-18 /s} = 4.4 x 10^17 s
Which, when converted, is about 1.3 x 10^10 yrs. or 13 billion years in age.
Smith’s next point of bafflement concerns gravity and “how it could change in a star unless it’s imposed from outside”.
But think of a star like a gigantic onion with multiple layers. The layers at the top or near the surface are lighter, because they have lighter gases which aren’t so compressed. But as one piles additional layer upon layer the weight of those layers presses down more on the layers toward the center of the star. Thus, the gravity is greatest near the stellar core and this helps to compress the gases in the core to their maximum pressure. Hence, it is precisely within the star’s core we expect the nuclear fusion reactions which provide its energy to occur.
A star, Main sequence – like the Sun – remains in balance and stability (what we call “hydrostatic equilibrium”) because each layer’s weight acting downwards is balanced by the radiation pressure (from the outward flowing radiation) acting outwards. I believe this is what Smith means when he argues against stars “balancing themselves against themselves”. Except they don’t: two distinct forces are balanced at each layer against each other.
Smith also appears to have problems grasping how “space dust” can agglomerate into a stable mass and then “combust” as a new star. Perhaps one of the best books he could get (as well as anyone else mystified by the process) is Isaac Asimov’s ‘The Collapsing Universe’. Using basic physics principles Asimov shows (Chapter 3, ‘Compressed Matter: Stars’ p. 55) exactly how the accumulation of dust and gas unfold – under the influence of gravitational attraction – for form a new star.
Another paragraph of mystification becomes clear once basic principles are learned:
Smith writes:
“I believe the purpose for the change from pure energy into the various forms of matter is to achieve balancing or stabilization in order to prevent collapse back to the original point”. But pure energy isn’t needed for this. . We know that the cosmological density parameter is crucial, viz.
OMEGA = rho / rho_ c
where rho is the observed cosmic density, and rho_ c is some critical value or threshold such that only if:
rho > rho_ c
the cosmic density reverses the expansion and forces a new cycle, starting with Big Bang. But current data, e.g. from Boomerang and other satellite detectors (See, e.g. 'Supernovae, Dark Energy and the Accelerating Universe', by Saul Perlmutter, in Physics Today, April, 2003,) shows that W » 0.3 or that: r = 0.3 (rho_c) I.e. that rho (less than) rho_c so there is no danger of the cosmos decelerating, and hence re-collapse. Hence, it is the residual mass of the cosmos (mostly in dark matter, such as black holes, intergalactic matter etc,) which inhibits any collapse, not “pure energy”.
Another mystifying comment from Smith is:
“Why assume the laws of physics are abandoned once you look into outer space?”
But who says they are, other than Smith? In fact, the laws of physics attain their state of maximal potency and application in space, and again – we have measurements to back up whatever claims are made. There is no “mystery” other than one deliberately confecting such, as Smith does. For example, he appears to question the rational basis of the Big Bang, and yet we have the evidence for the isotropic 2.7 K relic radiation – first observed by Penzias and Wilson at Bell Labs in 1965 and for which they won a Nobel Prize twenty-odd years later – which shows a cosmic fireball had to have originated some 13 billion years ago. That he (or others) may not be able to wrap their brains around that doesn’t make it less so, or counterfactual.
Like many other hobby- hunchers I see (those who come up with oddball conjectures to try to supplant accepted physics) Smith also displays an ambiguity in his terminology which conflates differing aspects of the physical world without a proper description or definition. For example, at the bottom of p. 18 he advances formation of an “energy field”. But there is no such thing. What we have are electrostatic fields, electro-magnetic fields, strong and weak nuclear fields, and gravitational fields. There is no …generic…”energy field” and none has been observed or measured. Neither is there such a thing as a “universe field” (p. 19 top). You can't simply make up entities like "fields" in your head and confer reality on them by fiat!
Smith rambles on that "we love mystery at the expense of logic” (ibid.) but this is codswallop. The thing most physicists hate above all is leaving any “mystery” out there so that assorted obscurantists, crackpots, cranks and others can parlay it into mumbo-jumbo….say like Michael Talbot’s alleged holographic “miracle” fields popularized in his Holographic Universe.
The truth is that physicists are ruthless in their logic applied to the cosmos, but this logic is always framed in its most concise and precise form – the language of mathematics. Physicists understand that without mathematics, such as tensor calculus, differential equations, non-commutative geometry and the like, we’d only really be able to theorize about one one thousandth of what we have. Mathematics makes the transfer from verbal conjecture to hypothesis to testing concrete.
Thus, it’s odd when Smith blurts that “math is likewise inefficient’. Perhaps only because he doesn’t know enough, and maybe never even took an advanced (e.g. college algebra) course, far less calculus or differential equations.
He appears to arrive at this nonsense by referring to a “pre-telescope European astronomer who proved mathematically that the sun and planets revolved around the earth..he accomplished this by adding loops in the orbits”
He is referring, of course, to the astrologer Claudius Ptolemy who generated a complex model (published in his Almagest) using “epicycles” (the added loops of which Smith writes) to explain the planetary motions, especially the retrograde motion of Mars (when it appears to be moving backward relative to the fixed stars)..
The problem, of course, is that the Ptolemaic system of epicycles is mythical and not based on the actual heliocentric system which follows from Newtonian principles of gravitation. It is here that the use of mathematics such as the differential equations of celestial mechanics, proves far more efficient and powerful than endlessly adding cycles that have no physical basis.
Thus it is that the over-complicated system of epicycles is rendered redundant once one understands and appreciates the planets move in elliptical orbits, not in circular ones. Ptolemy’s error was in trying to squeeze planetary motions into a “perfect” circular mold. Once this change to the actual physical orbits is made, then the appropriate equations, such as Kepler’s, e.g.
n(t – T) = E – e sin E
where n is the mean motion (in degrees per day or per second), t the referenced time, T the time of perihelion passage (e.g. closest point to the Sun), e is the eccentricity and E is the eccentric anomaly.
This can then be used in conjunction with others to arrive at the orbital elements for all the planets. These include: the eccentricity of the orbit, e (e.g. how elliptical it is or the deviation from circularity), the semi-major axis, a, or the mean distance to the Sun, the inclination (i) of the orbit – or the tilt of its plane with respect to the reference plane, and others.
Once these are known, I can then use the relevant equations, as I have done – whether in university projects or my own research – to accurately forecast the position of any planet well into the future – say the position of Jupiter in the sky on Feb. 1, 2100.
This is something Ptolemy and his epicycles could never do, and certainly not to the accuracy I can attain – an accuracy, by the way, that enables us to land complex Rovers on Mars, and mount close flybys of other worlds.
This alone skewers Smith’s claim that “mathematics is more of a copy machine than a discovery tool”
For his info, without the mathematics of tensors, general relativity would have remained a wild speculation and never attained theory stage. Without the basis of complex analysis neither plasma physics or quantum mechanics would have attained the maturity they have.
What Smith’s foray into the universe shows, if nothing else, is that a little knowledge is a dangerous thing – if it leads one to accept a perception of the cosmos totally fabricated from vague hunches, professed “common sense” and a mish mash of whacky ideas and terms …picked up from who knows where.
A final suggestion to Smith: there are terrific online courses in astronomy and physics available at the Yale University Open Course site:
http://oyc.yale.edu/courselist
See, e.g. the Astrophysics course at the top and Fundamentals of physics I,II lower down.
Even if you’re not mathematically adept, exposure to even some of these principles, concepts and illustrations will dispel at least some of your misconceptions about the cosmos! The question for you to address is: Do you wish to persist in these pet, subjective misconceptions ….or do you want to remove the blinders?
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