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Gravity's Engines
We’ve long understood black holes to be the points at which the universe as we know it comes to an end. Often billions of times more massive than the Sun, they...
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Editor's note: This article originally appeared in the March 1961 issue of Scientific American.
In the days when civilized men believed that the world was flat they had no reason to think about gravity. There was up and down. All material things tended naturally to move downward, or to fall, and no one thought to ask why. The notion of absolute up and down directions persisted into the Middle Ages, when it was still invoked to prove that the earth could not be round.
The first ray of light to pierce the mist of scholastic ideas about falling bodies issued from the work of Galileo Galilei. Since free fall was too fast to measure directly, Galileo decided to dilute the motion by studying bodies placed on an inclined plane. He argued—and at the time it was a novel argument—that since a ball resting on a horizontal surface does not move at all, and since a ball falling parallel to a vertical surface moves as fast as it would if the surface were not there, a ball on an inclined surface should roll with an intermediate speed depending on the angle of inclination. Letting balls roll down planes tilted at various angles, he observed their rates of travel and the distances covered in different time intervals, which he measured with a water clock. The experiments showed that at any angle the speed increases in direct proportion to time (counted from the moment of release) and that the distance covered increases in proportion to the square of the time. Galileo also observed that a massive iron ball and a much lighter wooden ball roll down side by side if released simultaneously from the same height on the same inclined plane.
As another way to dilute free fall he employed simple pendulums-weights suspended by thin strings. Here the steepness of the arc along which the weight travels is adjusted by changing the length of the string. Pendulums of the same length proved to have the same period of oscillation even when the weight was varied, a result in agreement with the outcome of the inclined-plane experiments. From all these observations Galileo was Ied to infer that in free fall all material bodies, light or heavy, also move in exactly the same way. This idea directly contradicted the opinion of the then prevailing Aristotelian school of philosophy, which held that heavier bodies fall faster than light ones. According to the celebrated legend, which may or may not be true, Galileo climbed the leaning tower of Pisa and dropped a light and a heavy ball, which hit tile ground Simultaneously, to the consternation of contemporary philosophers.
Newton's Law of Gravity
These studies laid the foundation for the science of mechanics. The main structure was erected by Isaac Newton, who was born the year Galileo died. With his laws of motion Newton introduced the notions of force and of inertial mass. When a force is applied to material bodies, it changes their speed or direction of motion or both. Their inertial mass opposes these changes. Newton stated that the rate of change of velocity (acceleration) of an object is directly proportional to the force acting on it and inversely proportional to its mass. Doubling the force doubles the acceleration; doubling the mass cuts the acceleration in half; if both force and mass are doubled, the acceleration is unchanged. In the light of this law Galileo's conclusion about free-falling bodies implies a fact that is usually taken for granted, but which is actually very curious; namely, the weight of a body (that is, the gravitational pull of the earth upon it) is strictly proportional to its inertial mass. Otherwise an iron and a wooden ball of the same size would not fall at the same rate. If the two objects have the same acceleration when they are dropped, the inertial mass opposing a change of motion in the iron ball must be greater than that in the wooden ball in exactly the same proportion that the downward force on the iron ball is greater. This proportionality is far from trivial; in fact, it holds true only for gravity and not for other familiar forces such as those of electricity and magnetism. Thus while an electron and a proton would fall with equal acceleration in a gravitational field, when these particles are placed in an electric field the electron is accelerated 1,836 times' faster.
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33 Comments
Add CommentAssumptions relating to the properties and physics of gravity are based upon assumptions yet to be proven. They are theories rather than scientific fact. The physical basis of black holes based upon gravity are, also, assumptions. Could it be that gravity and light and matter are CREATED in black holes as was the universe created under similar circumstances? Yes, it is possible. Perhaps, in a hundred years scientists will laugh at the naivete of the scientific community that made the aforementioned false assumptions with the result that they came to the false scientific conclusions as to the physical properties of gravity and the physics of gravity itself.
Reply | Report Abuse | Link to thisAh, and where was that 1st black hole? Where did it come from? Was it CREATED too? All bow down, right?
Reply | Report Abuse | Link to this@archimedes, there are few scientific "facts" as you may or may not understand; there are only theories supported by empiric evidence. Scientific truths may change with the preponderence of evidence provided over time. Currently assumptions made based on Einstein's theory have held true again and again. There is no reason to abandon those principles unless you are bringing forth new data that demonstrates Einstein's folly? You seem to assert that the assumptions discussed here, based on Einstein's theory, are likely to be found false. Care to offer any rationale? Otherwise, your thinking seems rather magical or quite speculative and not really all that credible.
Reply | Report Abuse | Link to this<<For example, the earth, in its orbital motion around the sun, should emit about .001 watt, which would result in its falling a millionth of a centimeter toward the sun in a billion years!>> [page 6 of 9 in the web version]
Reply | Report Abuse | Link to thisA planet that's lost energy should be further from the sun, no? Tidal energy transfer leads the moon-earth apart.
Can't be right all the time.
It would be nice if SciAm bothered to edit this article for scanning errors, including the "I ed" instead of "led" on the first page, and the many problems with exponents of ten. My charity publishes a newsletter with better copy editing, and we get no advertising money and an annual budget of $3000.
Reply | Report Abuse | Link to thisThe discovery of anti-mass and anti-gravitation would be especially interesting, as that would also imply the existence of anti-velocity, anti-acceleration, anti-momentum, etc. All of these effects are directional, their antithetical effects would require the existence of an anti-direction. Enough, already!
Reply | Report Abuse | Link to thisArchimedes: You ain't no Archimedes!!
Reply | Report Abuse | Link to thisPeterT
Since this article was originally published, it has been learned that the rate at which the universe is expanding has speeded up. Like many things in science, at this time, this is counterintuitive. So much to learn & I want to know now. Or at least before I run out of daylight.
Reply | Report Abuse | Link to thisHow do I get a copy of The Mössbauer Effect," by Sergio De Benedetti; SCIENTlFIC AMERICAN, April, 1960
Reply | Report Abuse | Link to thisYes I subscribe to sciam. The archives go back to 1993.
DURGADAS DATTA published --MISJUDGEMENTS BY NEWTON and BALLOON INSIDE BALLOON THEORY OF MATTER AND ANTIMATTER UNIVERSE in ASTRONOMY.NET in year 2002 . The links are available in durgadas datta face book. GRAVITY and RE CYCLIC UNIVERSE is fully explained and scientists are working on this theory in LHC and NASA.
Reply | Report Abuse | Link to thisActually Gravity is related to Electrostatics, not elecrromagnetics.
Reply | Report Abuse | Link to thisWith an electrostatic potential I can remove an object from clinging to earth. The limestone covers that all the pyramids once had were all removed by lazy people that came to live in Egypt. They built their dwellings with it. No way were the "Egyptians" proud of what the Atlanteans had built around 12,000 years ago. No matter what any person, claiming to be an expert, says.
Hello, JDWYER,
Reply | Report Abuse | Link to thisLook at >One Terminal Capacitor< and also at
>www.rexresearch.com/hiddimk/hiddink.htm
InquiringConstrctivist: "A planet that's lost energy should be further from the sun, no? Tidal energy transfer leads the moon-earth apart."
Reply | Report Abuse | Link to thisNo, just as it takes energy to lift a satellite into orbit, it takes energy to move a planet farther from the sun. Losing energy brings it closer, but it moves faster, which is counterintuitive. However, it also follows a shorter path, so it's total energy is less.
The move is moving farther from the earth because the some energy is being transferred from the earth to the moon. The moon is moving farther away from the earth; in return the earth's rotation is slowing slightly.
I'm sorry, but all civilized persons in the old times , starting from the ancient Greek civilization knew that the Earth was round, only some nearly illiterate people in less civilized times thought that it was flat. The concept of particles that are positive to gravitational forces and others that reject it, is contained in a novel by Jules Verne, in which the main character builds a ball , having one side attracting bodies and other rejecting them, that allows him to fly and move at his will just by tilting the ball. He called this forces pos and neg.
Reply | Report Abuse | Link to thisBlack hole and Big bang.
Reply | Report Abuse | Link to this============== ....
1.
A black hole is a theoretical region of space in which the
gravitational field is so powerful that nothing can escape.
2.
Hawking Radiation theorizes that black holes do not,
in fact, absorb all matter absolutely; they give off some
return matter.
3.
Once upon a time, 20 billions of years ago, all matter
(all elementary particles and all quarks and their
girlfriends- antiparticles and antiquarks, all kinds of
waves: electromagnetic, gravitational, muons…
gluons field ….. etc.) – was assembled in a ‘single point ‘
The reason of this unity is gravitational force.
4.
Questions :
How did the ‘single point ‘ create if the matter
can escape from any strong gravitational force?
==========.
Best wishes.
Israel Sadovnik. Socratus.
====================== .
Strange physic’s contradiction
Reply | Report Abuse | Link to this1
On the one hand :
The particles in the Universe are more than antiparticles
/ Baryon asymmetry /
2.
On the other hand:
Dark matter in the Universe is more than visual matter
Question :
Does one physic’s hand know that the other hand do ?
====== .
Best wishes.
Israel Sadovnik. Socratus.
====================== .
Hi, ennui - I couldn't find the page you referenced, the site does exist and did contain a tabbed link to a 'New Gravitational theory' (Ying/Yang). Looking back again, that tab has disappeared. Curious site. I did find a lot of anti-gravity links, but didn't pursue them.
Reply | Report Abuse | Link to thisThe Ying/Yang theory of gravity I briefly saw suggested that the attractive force of gravitation required that a repellent force also exist.
Actually, Newton didn't really believe in a an actual attractive force - he simply required an attractive effect to analytically describe the effects of gravitation.
This article's subtitle states:
Reply | Report Abuse | Link to this"Albert Einstein showed that gravitation can be interpreted as a geometrical property of spacetime."
With all respect due to George Gamow (or past or present SA editors), IMHO it is more correct to state that he mathematically described the _effects_ of gravitation using a system of spatial and temporal coordinates to quantify a dimensional distortion of spacetime that imparts kinetic energy to matter.
I'm more interested in the interaction of physical entities. I think that gravitation can best be mechanically described as the localized contraction of the kinetic energy permeating space produced by the potential energy of aggregated mass. Similarly to the linear contraction of localized spacetime produced by the acceleration of mass, the (at medium scales) typically spherically symmetrical aggregation of mass produces the radially directed contraction of spacetime kinetic energy. This external field of kinetic energy in turn tends to locally aggregate mass by imparting velocity to it directed to the local collective center of mass.
So, each object of mass is encompassed by a proportional external field of kinetic energy, directed to its collective center of mass. Put two objects next to each other and you have the interaction of two external fields of independently directed kinetic energy.
There is no physical attractive force or a repellent force, only the compression of spacetime between objects producing a locally directed accelerating force. This mechanical model of physical gravitation conceptually integrates the effects of the unphysical 'attractive force' employed by Newton and the unphysical 'spacetime curvature' employed by Einstein.
By the way, you might have noticed that low mass objects dropped to the Earth fall at essentially the same velocity. That is because their gravitational fields have little effect and they are both identically accelerated by the Earth's external field of kinetic energy. I don't understand why that puzzled George Gamow so, but then I only have a simple understanding of physics.
Reply | Report Abuse | Link to thisAlso notice that comparably massive objects, such as two stars (I understand most stars are actually binary pairs), seldom directly collide: instead they end up orbiting each other, at least for a long time. In my preceding mechanical model of gravitation, the external fields of kinetic energy are actually directed to the collective center of mass. Combined with any independent relative velocity, the directional interaction of kinetic energies effectively produces angular momentum and orbital motion.
I do commend SA for reposting this highly understandable, cohesive discussion of gravitation produced prior to the 'discovery' of observational data that still exceeds our ability to properly interpret it, leading to the interminable mess of imaginary dark matter, dark energy, dark flow, etc.
Reply | Report Abuse | Link to thisI concur with that. Notice it was first published thirty years ago when SA was truly a science publication. Now, anything they publish has to be judged in light of the garbage science they foster. You can no longer trust anything they publish. A great shame.
Reply | Report Abuse | Link to thisThrough a fairly long lifetime I have found that those who most vehemently call things "theories, not facts", particularly in the works of Einstein and Darwin, are simply lacking the understanding or the education to BUILD that understanding, of what comprises which and how broad the gray area is when they seek a crisp boundary between the two. Only when there is a vast improvement in teaching critical thinking skills from the beginning of education will there be any change.
Reply | Report Abuse | Link to thisThe quantum source of mass and gravitation are not yet understood, except as the nearly 60 year old hypothetical Higgs mechanism requiring an undetected Higgs boson to mediate the transfer of gravitational effects. It may be most instructive to note that the gravitation described by general relativity (and the mechanism for producing its physical effects I suggested previously) require not direct interactions among matter but the active participation of some kinetic energy or at least dimensional distortion of external spacetime.
Reply | Report Abuse | Link to thisThis external participation contrasts with the other fundamental interactions of matter, electromagnetism, the strong and weak, all of which which have been demonstrated to be directly imparted by the exchange of mediating particles. As I understand, including gravitation in quantum mechanics produces the collapse of all matter.
This indirect participation of some property of external spacetime may indicate that gravitation is unlike the other forces of matter. I'm most intrigued by the correspondence between the perceived dual particle-wave nature of matter, their respective propagation requiring kinetic emission energy and their stationary potential energy characterized as mass: where does the kinetic energy of waves go when matter is localized? I suggest it is converted to the potential energy of mass.
Quantum mass may be an encompassing energy imparting stationary spin to particles that is distinct from particle energy and its inherent characteristic properties.
very much enjoyed this article(except for the decimal places;-) glad to see someone do this...Thanks George...
Reply | Report Abuse | Link to thisWow jtdwyer your comments are absolutely ridiculous. Anti-velocity, anti-momentum, anti-direction? You know nothing about physics.
Reply | Report Abuse | Link to thisWow, I presume that other readers recognized that my purpose was to point out the absurdity of anti-gravity. How absurd that you failed to do so...
Reply | Report Abuse | Link to thisEntropy, Vacuum, Quantum Gravity,
Reply | Report Abuse | Link to thisSuperconductivity and Star formation.
=================...
1.
Henry Poincare named the conception of "entropy "
as a " surprising abstract ".
2.
Lev Landau (Dau) wrote:
" A question about the physical basis of the
entropy monotonous increasing law remains open ".
3.
One physicist said :" The entropy is only a shadow of energy.
4.
The mathematician John von Neumann said to
"the father of information theory" Claude Shannon:
" Name it "entropy" then in discussions
you will receive solid advantage, because
nobody knows, what "entropy" basically is ".
==========..
1.
Between 1850 - 1865 Rudolf Clausius published a paper
in which he called " The energy conservation law" as
" The first law of thermodynamics". But in our nature the
heat always flows from the higher temperature to the
lower one and never back. In our everyday life we don't see
the heat itself rises from cold to hot. So, it seemed that
in thermodynamics " The energy conservation law"
wasn’t kept, this law was broken. But Clausius had another
opinion. He thought: I know people believe that this process is
irreversible, but I am sure that " The energy conservation law"
is universal law and it must be correct also for thermodynamic
process. So, how can I save this law ?
Probably, in the thermodynamic process there is something
that we don't know. Maybe, there is some degradation
of the total energy in the system which never disappears .
Perhaps, there is some non-useful heat, some unseen process ,
some unknown dark energy , some another form of potential
energy/heat itself which can transform heat from the cold
body to the warm one. I will call this conception as " entropy"
and it will mean that changes of entropy (dS) can be calculated
for reversible process and may be defined as the ratio of the
quantity of energy taken up (dQ) to the thermodynamic
temperature (T), i.e. dS= dQ /T.
And because I don't know how this process goes I won't call
it as a law but as " The second principle of thermodynamics "
which says that " the entropy of an isolated system always
increases ". Another version: " No process is possible
in which the only result is the transfer of heat from a hotter
to a colder body. It is possible some reversible process which
is unknown now ."
2.
Between 1870 - 1880 Ludwig Boltzmann said:
" Clausius is right. But I can add more to his entropy conception.
First.
According to Classic physics when an isolated thermodynamic
system comes to a thermal equilibrium all particles stop their
moving. From one hand it is correct. But the system cannot be
at thermal equilibrium (in the state of thermo death) all the time.
The situation in the system must change.
Therefore I say that at the thermal equilibrium the entropy
(some unknown dark/potential energy ) of the system will
reach maximum and as a result , the thermal equilibrium
of the system will change.
Second.
I don't know how exactly the thermal equilibrium of the system
changes. But I can give probabilistic / statistical interpretation
of this changing process. I can write " The second principle of
thermodynamics" by a formula: S= k log W and this formula
says:" the entropy ( heat) of the system is the collective result of
mechanical motion and friction of all the particles (k)."
I will call it as " The second law of Thermodynamics."
3
In 1900 Max Planck said:
Clausius and Boltzmann are both right.
But all my life I worked almost exclusively on problems
related to thermodynamics. And I am sure that the " The second
law of Thermodynamics" , concerning entropy, is deeper and it
says more than is generally accepted. I am sure the Boltzmann's
probabilistic /statistical version of "The second law of
Thermodynamics " is not completed, is not final.
Please, look at the graph of the radiation curves of the " black body".
They are very similar to those curves which are calculated
by Maxwell for the velocity (i.e. energy) distribution of gas
molecules in a closed container. Could this black body radiation
problem be studied in the same way as Maxwell's ideal gas....
...electromagnetic waves ? This problem of connection between
radiation of black body and Maxwell's Electrodynamics theory
doesn't give me peace. Maxwell's theory can tell everything
about the emission, absorption and propagation of the radiation,
but nothing about the energy distribution at thermal
equilibrium. What to do? How to be ?
After trying every possible approach using traditional
classical applications of the laws of thermodynamics
I was desperated. And I was forced to consider that the
relation between entropy, Boltzmann's probability version
and Maxwell's theory is possible to solve by suggestion ,
that energy is radiated and absorbed with discrete
individual quanta particle ( E= hf). So, now I must write
" The second law of Thermodynamics " by formula:
hf = k log W.
But if I look to the Clausius inequality I see that entropy
is energy divided per temperature.
So the formula hf = klogW is hf = kT logW I think.
I was so surprised and skeptical of such interpretation
the entropy that I spent years trying to explain this result
in another , less revolutionary way. It was difficult for me
to accept this formula and to understand it essence .
It was hard for me to believe in my own discovery.
==================..
My conclusion.
How to understand this formula?
Which process does formula (hf = kT logW ) describe ?
1.
In 1877 Boltzmann suggested that the energy/mass state
of a physical system (of ideal gas ) could be discreted.
This idea was written with formula: R/N=k. It means:
there are particles with energy/mass state (k) in physical
system of ideal gas . They don’t move, they are in the
state of rest.
2.
In 1900 Planck followed Boltzmann's method of dividing.
Planck suggested that energy was radiated and absorbed
with discrete "energy elements" - " quantum of energy"-
- " Planck's action constant"- (h) . This fact means:
electron produces heat, setting in mechanical motion and
friction all particles. This fact is described with Planck's
formula: hf = kTlogW.
3.
In which reference frame does this process take place?
In thermodynamical reference frame of ideal gas and
black body (M. Laue called this model as Kirchhoff’s vacuum).
Now it is considered that these models are abstract ones which
do not exist in nature. On my opinion these models explain
the situation in the real Vacuum (T=0K) very well.
4.
For my opinion the formula (hf = kT logW ) says:
a)
The reason of " entropy" , the source of thermal equilibrium's
fluctuation , the source of Vacuum fluctuation is an action of
the particle /electron, which has energy: E = hf.
b)
The process of Vacuum fluctuation depends on collective
motions of all particles (k) and will be successful if enough
statistical quantity of Boltzmann's particles ( kT logW)
surround the electron.
c)
Which process does the formula (hf = kT logW ) say about ?
This formula describes the possibility of realization of
macro state from micro state. This formula explains
the beginning conditions of gravitation,
the beginning conditions of star formation.
hf = kT logW.
hf > kT logW.
hf < kT.
Once again.
The electron changed the temperature of the surface in local area.
Now this local area has Debye temperature: Q(d)= h*f (max) / k.
In this space a grain of gravity theory is hidden.
The scheme of gravity:
E=h*f --> He II --> He I -->
Plasma reaction... --> Thermonuclear reactions ...-->......etc.
( P. Kapitza , L. Landau , E.L. Andronikashvili theories).
(Superconductivity, superfluidity.)
d)
Thanks to Entropy the homogeneous Vacuum is broken.
Thanks to Entropy the micro process changes into
macro process.
Thanks to Entropy the stars formation takes place.
Thanks to Entropy " the ultraviolet catastrophe" is absent.
Thanks to Entropy our Milky Way doesn't change into radiation.
Thanks to Entropy the process of creating elements takes place.
Thanks to Entropy the process of evolution is going.
e)
One physicist said :" The entropy is only a shadow of energy“.
Maybe now somebody can understand why entropy is a shadow.
And maybe now somebody will understand why
" The Law of conservation and transformation of energy"
is also correct for thermodynamic system.
f)
Why is " The second law of Thermodynamics"
so universal? Because it is based on
" The Law of conservation and transformation of energy"
And this law is not the simple accounting solution of debit and credit.
The sense of this law is dipper and it says more than is usually accepted.
=====================.
Best wishes.
Israel Sadovnik Socratus
=======================.
This may sound funny, But I do not believe that we are held to this earth as Newton states . we are pressured down by our atmosphere as Einstein stated a 100 years ago . And you can't manipulate something thats not real.
Reply | Report Abuse | Link to thisI agree in any case. You might be interested in my comment #20 describing my current conception of the gravitational force as an external pressure from space, contracted by the potential energy of mass. I also think that this mechanism can be used to explain the imaginary attractive force used by Newton in his analytical description of gravitational effects. I wasn't really aware of Einstein's mention of external pressure, except that, as I understand, he said that the effect of gravitation is equivalent to acceleration.
Reply | Report Abuse | Link to thisThere must be something more physical mechanically producing the effects described by imaginary forces and abstract dimensional coordinates...
The following is a proposition unproved: the summation over the charge distribution of mass 1 and mass 2 does not produce a force that we would call gravity, i.e. this is the present assumption of modern physics. This assumption is obviously without merit. In other words, quantum mechanically, gravity is a separate force of nature. But exactly what does this really mean. The force due to charges of mass (i) and mass (j) is something like:
Reply | Report Abuse | Link to thisF=∑_1^I▒〖∑_1^J▒1/(4πϵ_0 ) (q_i q_j)/〖r_ij〗^2 +q_i v_i×B_j+q_j v_j×B_i 〗 11
And that the above is different from the gravitational does not follow as simply by saying that it was shown to be the case quantum mechanically. In fact we know that quantum mechanics is not a derivable physical theorem or law, only a very good method to imply statistics of the microscopic.
One may simplify, in order to theorize if this yields a force that we could call gravity as:
F= K/(2πϵ_0 ) (|Q_1 Q_2 | δ^2)/〖r_12〗^4 12
That is:
F=|Q_1 Q_2 |/(4πϵ_0 ) {[2/〖r_12〗^2 ]-[2/((〖r_12〗^2+δ^2 ) )]}=1/(2πϵ_0 ) (|Q_1 Q_2 | δ^2)/〖r_12〗^4 13
Letting 〖r_12〗^4≫〖r_12〗^2 δ^2
I meant the result to be:
Reply | Report Abuse | Link to thisF = (1/2Pi Epsilon)(|Q1Q2|delta^2/r^4)
where delta = 10^-39 meters for the planet earth. I used superposition, Avogadro, and the distribution of the elements for the planet earth for the charge distributions and it will be obvious the the masses will comply to have the like charge centers further apart than the unlike charge centers. Thus always an attractive force.
That is + -
_ +
and the separation of the charge centers within each mass as delta with r as the distance between the masses.
Why is it that the gravity of the moon apparently can affect 2/3rds of the earth's surface but not our weight as it passes by?
Reply | Report Abuse | Link to thisSatellite readings of ocean levels seems to indicate
that tides are more likely to be the earth's response to the moon and sun orbits. The hypothesis of a dynamic ether offers a more logical account of the process.
Dear Carlyle,
Reply | Report Abuse | Link to thisTo have any hope of finding reasons/and or connections between dark energy, dark matter, dark flow, black holes the Big Bang, a singularity and gravity itself, one has to seek alternate interpretations to current observations.
One such interpretations begins with the statement that "The universe is a disturbed field of pure energy seeking equilibrium" To my mind --- how else could it be?