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Dark Matter Dark Energy The Universe...matter in a small patch of sky. Dark Energy Survey using Dark Energy Camera in Chile Red is dense . Evidence and Analysis •The outer stars

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  • Dark Matter Dark Energy The Universe

    cosmic speculation

    Bill McKeeman Presented to

    The New Hampshire Astronomical Society 24 Jun 2016

  • Observed Evidence and

    Cosmologists’ Analysis

    When you stand on the shoulders of giants, it is hard to see what is right in front of you.

  • Dark Matter

  • The outer galaxy rotates too fast

    Expected Actual

  • Gravitational Lensing (a galaxy behind a galaxy)

    (foreground galaxy nearly perfect lens)

  • Gravitational Lensing Analysis

    A special telescope looks for matter in a small patch of sky.

    Dark Energy Survey using

    Dark Energy Camera in Chile

    Red is dense

  • Evidence and Analysis

    • The outer stars of galaxies fall behind – (thus the spiral arms) – but not as far behind as expected

    • There must be more mass inside the galaxy – (its hard to go against Newton) – the supermassive central black hole is not enough – maybe galaxies contain invisible mass?

    • Dark Matter proposed 1933, still not found – Wimps? (Weakly Interacting Massive Particle) – Machos? (Massive Astronomical Compact Halo Object)

    » Tiny black holes? » Space junk?

  • Dark Energy

  • Big Bang


    First Light Galaxies

    Accelerating Expansion

    0 10-32 10-5 200 380000 3*108 1010 13.8 billion far future ------seconds------- -------------------------years---------------------------->

    First stars Now

  • Hubble Deep Field (two-week time exposure of an empty bit of sky)

  • Cosmic Microwave Background has black body frequency signature.

    The Universe must have been in thermal equilibrium when atoms formed.

    Radiation released in every direction from every point in the Universe.

    We observe just the photons that were pointed at us us from a spherical slice of the Universe

    when it was 0.1% of its present size

  • CMB Wavelength

    very red-shifted

  • Evidence and Analysis

    • Expansion of the Universe

    – red shift for speed (Hydrogen alpha line)

    – standard candles for distance (Type 1a novas)

    – coasting after Big Bang?

    • but eons ago it was expanding more slowly

    • pushed apart by something? – called Dark Energy since 1990s

  • Modern Instruments

    • Hubble – very long exposure shows very distant galaxies

    • Sloan Deep Sky Survey – extensive survey of part of the sky – (cannot see through Milky Way)

    • Spitzer infrared telescope – (can see through Milky Way)

    • Dark Energy Camera – analyzes gravitational lensing

    • Cosmic Microwave Background (COBE, WMAP, PLANCK) – (look for lensing effects) – (race condition -- which got there first: CMB or gravitational clumping?)

    • James Webb Telescope (2018 launch) – for stars red-shifted beyond visible light

  • Gravity

  • Newton’s Gravity

    • Proportional to included mass

    • At a distance, effect is distributed evenly over containing sphere therefore inversely proportional to surface area 4πd2.


    |a| = GM/d2: for large d (inverse square law)

    The rest of the Universe also contributes to |a|, but not significantly near this mass.



  • Current Theory

    • Mass bends space – each particle contributes – the contributions are additive… – …over the whole Universe

    • Gravity is the effect of curved space – sum up all the dimples

    • Universe is either very BIG or just FLAT – primitive man once thought the Earth was flat – we are all susceptible to the extrapolation fallacy – size is at least 10^11 light years

  • Some Geometry

  • 3D and 4D Spheres

    3D-sphere radius R

    • x2+y2+z2=R2

    • Contents (4/3)πR3

    • Boundary 4πR2

    – 2D

    – locally x, y

    4D-sphere radius R

    • w2+x2+y2+z2=R2

    • Contents (1/2)π2R4

    • Boundary 2π2R3

    – 3D

    – locally x, y, z

    Go in a straight line on the boundary of the sphere… …eventually return from the other direction.

  • Boundary of Spheres

    3D sphere radius R

    • d: surface distance

    • c: circle on surface

    • 2πRsin(d/R): circumference

    4D sphere radius R

    • d: space distance

    • s: sphere in boundary

    • 2πR2sin2(d/R): surface area

    side view top view



    min at d=0 max at d=πR/2 min at d=πR


  • Start of Speculation

    Ideas are Easy Observation and Analysis are Hard

  • Assume the Universe

    is closed --

    that it is the 3D boundary of a 4D sphere of radius R.

    (a sphere is easy to analyze;

    any convex deformation of a sphere would also work)

  • Gravity in closed spherical Universe of radius R

    • Proportional to included mass

    • Effect is spread over increasing area

    • Inversely proportional to area of enclosing sphere

    • |a| = GM/(Rsin(d/R))2 : 0

  • Milky Way Gravity (two maxes and a min)




    The gravity-containing sphere gets larger, then smaller.

  • AGF Antipodal Gravitational Focus

    • Every massive body is matched by an AGF

    on the opposite side of the Universe

    • Gravitational force near the AGF is: – the same magnitude as near the originating

    massive body

    – directed toward the massive source …

    – … therefore directed away from the AGF

    • In effect, an AGF repels matter

    • Nothing to see at the AGF

  • What Gravity Might Look Like (3D or 4D)

    • Imagine the smooth boundary of a sphere… – …as big as the universe

    • Place a particle – makes a dimple and an antipodal pimple

    • Place a second particle – another dimple and pimple…

    – …perhaps moving w/respect to first particle

    – (curvatures are additive over entire universe)

    • Add 10100 more particles

    • That lumpy, roiling, antisymmetric boundary is gravity

  • AGF acts like Dark Matter

  • MW AGF

    Milky Way

    Milky Way pulls matter away from its own AGF…


  • MW AGF






    Milky Way

    Milky Way pulls matter away from its own AGF…

    …therefore the corresponding matter AGFs migrate out of and away from Milky Way






    3 3





  • Galactic AGF: in words

    • Each galaxy has an AGF on the opposite side of the Universe

    • Each galaxy pulls matter away from its own AGF

    • The pulled matter has corresponding AGFs near that galaxy

    – those AGFs migrate away from that galaxy

    – a purely geometric effect

    • Thus each galaxy is cleared of, but is surrounded by, AGFs

    The net effect is that gravitational force

    directed toward galactic center is increased

  • AGF








    A galaxy surrounded by AGFs rotates like (but not exactly like) a galaxy with

    imbedded Dark Matter

    Gravity, from across the Universe, is focused at each AGF

    red means repel

  • Galactic Rotation

    • The result of a galaxy surrounded by AGFs is faster galactic rotation at the periphery, as observed.

    • Data and analysis needed for confirmation.

    – (that’s hard work)

  • AGF








    Stars nearest the largest AGFs…

    red means repel

    …should rotate faster

    Black dot is supermassive black hole at galactic center

  • How to find galactic AGFs

    • Re-analyze existing star motion data

    – Consider star velocity a vector field in galaxy

    – Look for variations by galactic longitude

    – Look for variations by galactic declination

    – Infer location and size of surrounding AGFs

    • large simulations

    • There is (surprisingly) very little star speed data.

    – Astronomers tell me no such data exists

    – Dartmouth Science Librarian could not find data

  • Anti-Galaxy

    • If you take each particle in a galaxy,

    • …reflect it across the universe to its AGF,

    • …make the mass of each particle negative,

    • …add up all the gravity, – (the sum of the pimples equals the sum of the dimples)

    • …you get the same gravity as the AGF. – mass of anti matter has not been directly measured –

  • Anti-Black Hole

    • The AGF of a black hole…

    – a perfect, spherical, reflector

    – …like those lawn ornaments.

    • Light cannot get into it

    • (Earth-mass black hole diameter: 1.772 cm)

  • AGF acts like Dark Energy




  • Superclusters are the largest gravitationally-bound structures

    in the Universe

    • Superclusters contain clusters – Clusters contain galaxies

    • Galaxies contain black holes and stars and space junk

    • Each supercluster has an AGF – causes itself to be centered in a void – has a negative lensing effect

    • stars seen “thru” a void are off to the side

    – repels nearby superclusters • effect is expanding Universe

  • Expansion Story

    • Universe is chaotic & dense after Big Bang

    – Inflates and cools

    – Matter condenses out of initial plasma

    – Hydrogen atoms form, CMB is released

    – Atoms clumps into stars, black holes and galaxies

    – AGFs cause cosmic “sort”

    • Initially insignificant

    • AGFs more effective as matter becomes more organized

    • Expansion accelerates, as observed

  • Speculative Summary

    • A galactic AGF repels nearby matter – clearing the galaxy of AGFs corresponding to that matter

    – increasing the inward-pointing gravitational forces

    – increasing the speed of stars at the periphery

    • Supercluster AGFs repel nearby superclusters – create void regions in space

    – cause the Universe to expand • rate depends on the distribution of matter

    • rate varies with time after Big Bang

  • References

    • Space’s Deepest Secrets, Science Channel 2016

    • Great Courses:

    – Understanding the Universe, Alex Filippenko

    • especially lectures 74 & 83

    – Dark Matter, Dark Energy, Sean Carroll

    • especially lecture 12


    • (extensive history of MW)

    • (NASA, Universe 101)

    • (blog to explain current cosmo theories)

    • (88 page history of dark matter)

    • SciAm SciAm SciAm…

    • wiki wiki wiki…

  • Q & A Some real physicists have been generous with their time

    • Q: These AGFs should be all around us, exerting their light and matter repelling effects -- but nothing like them has been observed

    • A: It is almost a conspiracy: our galaxy has pulled all the nearby AGFs just beyond easy viewing.

    • Q: What about the gravitational lensing detection of dark matter which shows 7x more Dark Matter than Bright Matter?

    • A: Light and matter react to gravity the same way, so a halo of AGFs around a galaxy would have an effect similar to dark matter in it, but 7x seems like more than AGFs can explain.

    • Q: What about the measured flatness of the Universe? • A: The error estimates for curvature are ±0.002 from flat. That is

    consistent with a very large closed universe. The AGF effects are independent of the Universe size. Besides, I do not see how to get to an infinite flat Universe from the Big Bang.

    • Q: Are you going to publish these ideas? • A: Not a chance. Journal standards are much higher than this.