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There IS a way to tell that Adanacia is an antimatter world, but it involves a couple of new ideas…

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Page 1: There IS a way to tell that Adanacia is an antimatter world, but it involves a couple of new ideas…
Page 2: There IS a way to tell that Adanacia is an antimatter world, but it involves a couple of new ideas…

There IS a way to tell that Adanacia is an antimatter world, but it involves a couple of new

ideas…

Page 3: There IS a way to tell that Adanacia is an antimatter world, but it involves a couple of new ideas…

There IS a way to tell that Adanacia is an antimatter world, but it involves a couple of new

ideas…

In the lesson “Medicine: The Next Generation”, you learned how some unstable nuclei become stable by

emitting positrons.

There are other unstable nuclei that emit electrons in order to become stable…

Page 4: There IS a way to tell that Adanacia is an antimatter world, but it involves a couple of new ideas…

One example of these is Cobalt-60. This nucleus contains 27 protons and 33 neutrons. When the nucleus decays, it produces an electron and an antineutrino. The nucleus

that remains is stable and is called Nickel-60:

Cobalt-60

Nickel-60 + +

Co-60

Ni-60 + e− −ν+

Click here for extra information about this decay:

Page 5: There IS a way to tell that Adanacia is an antimatter world, but it involves a couple of new ideas…

Nuclei have another property call “spin”. This property is a property of particles that has no analogue in our everyday experience. A full explanation of this property goes well

beyond the scope of this module, but for our purposes we can imagine that a nucleus “spins” in the way you are familiar with:

…in the manner of spinning top.

Page 6: There IS a way to tell that Adanacia is an antimatter world, but it involves a couple of new ideas…

We have mentioned this property because most of the electrons emitted

when a Cobalt-60 nucleus decays are emitted in a particular direction. If we look at Cobalt-60 spinning in the direction shown here:

Page 7: There IS a way to tell that Adanacia is an antimatter world, but it involves a couple of new ideas…

Co-60

We have mentioned this property because most of the electrons emitted

when a Cobalt-60 nucleus decays are emitted in a particular direction. If we look at Cobalt-60 spinning in the direction shown here:

Page 8: There IS a way to tell that Adanacia is an antimatter world, but it involves a couple of new ideas…

…then most of the electrons will be emitted directly upwards.

Co-60

We have mentioned this property because most of the electrons emitted

when a Cobalt-60 nucleus decays are emitted in a particular direction. If we look at Cobalt-60 spinning in the direction shown here:

Page 9: There IS a way to tell that Adanacia is an antimatter world, but it involves a couple of new ideas…

Now, in an antimatter world, instead of Cobalt-60, they would have what we would call anti-Cobalt-60:

anti-Cobalt-60

Page 10: There IS a way to tell that Adanacia is an antimatter world, but it involves a couple of new ideas…

anti-Cobalt-60

When anti-Cobalt-60 decays, the ANTIMATTER TWINS of the particles formed in the decay of Cobalt-60 are produced instead…

anti-Nickel

-60 + +anti-

Cobalt-60

anti-Co-60

anti-Ni-60

+ e+ ν+

Click here for extra information about this decay:

Now, in an antimatter world, instead of Cobalt-60, they would have what we would call anti-Cobalt-60:

Page 11: There IS a way to tell that Adanacia is an antimatter world, but it involves a couple of new ideas…

Not only that, but if we look at anti-Cobalt-60 spinning in the direction shown here:

Anti-Co-60

Page 12: There IS a way to tell that Adanacia is an antimatter world, but it involves a couple of new ideas…

Not only that, but if we look at anti-Cobalt-60 spinning in the direction shown here:

…then most of the positrons will be emitted directly downwards.

Anti-Co-60

Page 13: There IS a way to tell that Adanacia is an antimatter world, but it involves a couple of new ideas…

So here’s what you could ask the Adanacians to do:

Tell them to take the nucleus on their planet with 27 protons and 33 neutrons (remember, they do not refer to the “matter” on their planet

as “antimatter”)and to orient this nucleus in such a way that the particles that are

emitted are directed upwards (i.e., directly away from their planet):

Page 14: There IS a way to tell that Adanacia is an antimatter world, but it involves a couple of new ideas…

So here’s what you could ask the Adanacians to do:

Tell them to take the nucleus on their planet with 27 protons and 33 neutrons (remember, they do not refer to the “matter” on their planet

as “antimatter”)and to orient this nucleus in such a way that the particles that are

emitted are directed upwards (i.e., directly away from their planet):

Page 15: There IS a way to tell that Adanacia is an antimatter world, but it involves a couple of new ideas…

We then take a look to see the direction that the nucleus is spinning in.

Page 16: There IS a way to tell that Adanacia is an antimatter world, but it involves a couple of new ideas…

We then take a look to see the direction that the nucleus is spinning in.

If we see that it is spinning like this…

Page 17: There IS a way to tell that Adanacia is an antimatter world, but it involves a couple of new ideas…

We then take a look to see the direction that the nucleus is spinning in.

…then that nucleus is made of antimatter.

Page 18: There IS a way to tell that Adanacia is an antimatter world, but it involves a couple of new ideas…

Anti-Co-60

We then take a look to see the direction that the nucleus is spinning in.

…then that nucleus is made of antimatter.

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In our MATERIAL world:

Page 20: There IS a way to tell that Adanacia is an antimatter world, but it involves a couple of new ideas…

Co-60

In our MATERIAL world:

This will occur…

Page 21: There IS a way to tell that Adanacia is an antimatter world, but it involves a couple of new ideas…

Co-60

Co-60

In our MATERIAL world:

This will occur… but this will not.

Page 22: There IS a way to tell that Adanacia is an antimatter world, but it involves a couple of new ideas…

Co-60

Co-60

In our MATERIAL world:

This will occur… but this will not.

In the ANTI-MATERIAL world:

Page 23: There IS a way to tell that Adanacia is an antimatter world, but it involves a couple of new ideas…

Co-60

Co-60

Anti-Co-60

In our MATERIAL world:

This will occur… but this will not.

In the ANTI-MATERIAL world:

This will NOT occur…

Page 24: There IS a way to tell that Adanacia is an antimatter world, but it involves a couple of new ideas…

Co-60

Anti-Co-60

Co-60

Anti-Co-60

In our MATERIAL world:

This will occur… but this will not.

In the ANTI-MATERIAL world:

This will NOT occur… but this WILL.

Page 25: There IS a way to tell that Adanacia is an antimatter world, but it involves a couple of new ideas…

ANTIMATTER IS OFTEN CALLED “THE MIRROR IMAGE OF MATTER”.

Page 26: There IS a way to tell that Adanacia is an antimatter world, but it involves a couple of new ideas…

Hey,lookin’ good!

Hey,lookin’ good!

ANTIMATTER IS OFTEN CALLED “THE MIRROR IMAGE OF MATTER”.

BUT WHAT DOES IT REALLY MEAN WHEN WE SAY THIS?

Page 27: There IS a way to tell that Adanacia is an antimatter world, but it involves a couple of new ideas…

LOOK AT THE DIAGRAM ON THE RIGHT.

SEE IF YOU CAN DETERMINE HOW THE METHOD USED TO

CONFIRM THAT ADANACIA WAS AN ANTIMATTER WORLD AND THIS DIAGRAM ARE RELATED

TO EACH OTHER.

DOES THE DIAGRAM JUSTIFY CALLING ANTIMATTER THE

“MIRROR IMAGE” OF MATTER?

IF SO, WHAT DOES THIS “MIRROR” ACTUALLY

“REFLECT”?

FEYNMAN MIRROR COMPANY