Hendrik Lorentz and Martinus Veltman meet at the symposium celebrating the centennial anniversary of the Nobel prize for Zeeman and Lorentz (Leiden, 11 October 2002).

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lorentz_veltman_7 zeeman_experiment

Text of the dialogue between Tini Veltman and Henk Lorentz. (Here is the full text of the lecture.)

Veltman, alone on the stage, starts his lecture on "Was Lorentz our first particle physicist?" The audience was not suspecting the strange meeting that would follow...

Veltman: The time of Lorentz seems far in the past, and yet it is 
not really that long ago. Here is what happened to me.

I am a member of a club for retired people. Two days after I got the Nobel
prize we had a meeting. When I sat down my neighbour told me:

"I wonder if when you die they will wrap the streetlights in black cloth."

I asked: Why that?

"Well, I remember that when Lorentz was buried the burning street lamps along
the funeral route through Haarlem were draped in black cloth."

My friend at that club did live in Haarlem at the time of Lorentz'
death in 1928. As a 10 year old boy he saw the funeral procession.
Since Einstein and Rutherford spoke at the grave he might have seen
them as well.

I told him that I would be very surprised if they did that for me
in Bilthoven.

For the purpose of this symposium I read the Nobel lecture of Lorentz.
First I was surprised to see that Lorentz knew that Rontgen rays are a
shortwave version of electromagnetic radiation. Furthermore
Lorentz still believed firmly in the existence of the ether. But
what hit me most was the enormous gap between the knowledge then
and now. I would have big difficulties telling Lorentz anything
about physics as we know it today.

{Photo of Lorentz on overhead projector.}

Imagine for a moment that I was talking to the Lorentz of 1902.

{Karel Gaemers comes from behind, and whispers something in Veltman's ear.}

V: What !!! ??? !!!

V: (to audience) I am told that some man claiming to be Lorentz
was found lost in the middle of Leiden.

{Lorentz enters the auditorium and walks up to a position 
opposite Veltman.}

V: Prof. Lorentz !!! 	!!!

L: De Heer Wells uit Engeland kwam naar Leiden om mij zijn tijd-reis
machine te tonen. Hij gaf me een uur in Leiden 100 jaar in de toekomst.
Ik herkende niets meer. Vriendelijke omstanders hebben mij hier gebracht
waar blijkbaar een herdenking plaats vindt.

V: Prof. Lorentz, dit is een internationaal publiek.

L: Wel, wat wilt U dat ik spreek, Frans of Duits?

V: Uh... Engels.

L: Remarkable. My English is not very good, but I will try.

V: Prof. Lorentz, reading your Nobel lectures I saw that you knew
that Rontgen radiation was a short wave form of electromagnetic
radiation. How did you know?

L: This became clear after the experiments of Mr Haga and Mr Wind
from Groningen.

V: Aha. Would you be interested if I try to tell you what we know now?

L: Of course!!!

V: Let me start telling you something about the known forces. In addition
to gravitation and electromagnetism we have discovered that there exist
other forces. For example there is the so-called weak force.

L: Tell me about it.

{Projection of Coulomb scattering}

V: First, ordinary Coulomb scattering, scattering of an electron
on a proton.

L: Proton? What is that?

V: Excuse me. A positively charged hydrogen ion.

L: I understand. I suppose that the wavy line represents the
Coulomb potential.

V: Right. Now here a similar process involving the weak force.
A neutrino scattering of a neutron...

L: Neutrino? Neutron?

V: Excuse me. A neutron is a neutral version of a hydrogen ion,
it is actually part of Becquerel radiation. The neutrino is like an
electron but without electric charge. It also is produced in
Becquerel radiation. It is massless.

L: No mass?? How is that possible?

V: Uh.. Excuse me. It has a very, very small mass.

L: Very interesting. But what happens then?

V: Well, these weak forces do actually change particles.
So the neutrino becomes an electron and the neutron changes into
a proton.

L: I suppose that the red line represents the potential of this
new weak force?

V: Right.

L: How strong is this force?

V: It is a little bit stronger than the Coulomb force.

L: Why then do you call it a weak force?

V: Let us not go into that.

L: Well, you are not very clear. Can you tell me then if
this new force is repulsive or attractive?

V: Uhhh... I do not know.

L: Incredible. There is a new force and you do not even know
if it is repulsive or attractive ! Let us start on something else.
What about the ether?

V: The ether does not exist.

L: Not even a single one?

V: None at all.

L: What !!!  So space is empty?

V: Uh.. Actually, no. There is a field in it called the Higgs field.

L: Perhaps this is just another name for the ether?

V: No, it has different properties. For example, photons do
not interact with this Higgs field.

L: Photons?

V: Excuse me. Electromagnetic radiation does not interact with
this Higgs field.

L: But does it interact with anything else ?

V: It interacts with all matter.

L: Well. that makes things easier. So you can do
experiments to establish with what speed we move with respect to this
Higgs field.

V: No, because this field is a scalar with respect to Lorentz

L: What do you mean: "scalar"?

V: Excuse me. This gets difficult. Let us not go into that.

L: Sir, I cannot say that you gave me much information. I am not
sure that you understand what you are talking about. I have to
go now. Let me ask you a question. Where are you from?

V: Waalwijk.

L: Aha. This is in Noord Brabant if I am not mistaken. Where did
you study, at least if you did.

V: I went to the University of Utrecht.

L: Aha. I understand. Perhaps you should attend some lectures
in Leiden. Well, I have to go.

{Lorentz goes away, muttering loudly.}

L: Well, I suppose that not everybody is made to be a Nobel
prize winner.