Evening star. [volume] (Washington, D.C.) 1854-1972, 1931-06-28
Likened to String of Speeding Base
Balls.
BY. HOWARD w. BLAKESLEE,


BY HOWARD w. BLAKESLEE,
Associated Press Science Editor.
NEW YORK, June rs (4).-Sir Chand-
raSekhara Yenkata's discovery is much
like finding that light instead of being
irnmaterial is a string of base balls,
thrown by big league pitcher, whizzing
and curving as they speed ahead.
This idea that light is both particles
and waves is not new, but there has
been a wide gap between the known
wave characters of light and its particle
attributes. So wide a gap that stand
ing joke has it that scientists regard
light as waves on the first three days
of the week, as particles on the sec
ond three and as both on Sundays.
Some of this gap may be bridged by
Sir Chandrasekhara's discovery. He
opens the door upon new world OF
exploration.
The angular momentum-in which he
finds the new facts about light-de-
ponds partly on distribution of mass
in a particle. The shape of the particle
is likely to be factor in this distrihu-
ton of mass. So, finding angular
momentum in light is really to dis
cover some more of the ways in which
1t acts like a string of particles.
Angular Momentum Obtained.
bII6
Is obtained by multiplying mass, inertia
and the angular velocity. The inertia"
in these figures is intimately associated
with mass and shape.
The angular velocity is the angle
through which an object turns in one
second of time.
Since it is. difficult to think of a
light wave as having anything in COM
mon with angular momentum" DR..
H. II. Sheldon, professor of physics of
New York University, suggests the base
ball analogy as giving laymen an idea
OF the novelty and Importance of the
discovery.
The possibility of using the new
knowledge about light is not neces-
sarily an idle dream. Few of Natures
phenomena differ more radically in
their effects than the different wave
lengths of light. Yet little is known
of the reasons why. and now an ad-
ditional road is open to search for the
cause. -...
Varying Short Waves.
For example. only the very short
waves-the ultraviolet-cause sunburn
and tan. There are literally thousands
of this class Of waves alone, each diff
ferent from all the others. For sew
eral years physicists and medical men
have sought to classify them better, so
as to learn precisely which wave lengths
do the most effective work. and why
Red light on a Photographic plate is
another familiar example. It may
shine all day without, affecting the
sensitive plate, although a tiny amount
OF shorter wave lengths will ruin the
plate instantly.
The scientific explanation is that
light is divided into municipalities
each of a different energy. These quanta
do their work like coins in a slot ma
chine. Where they dc. not at they pass
by harmlessly.
The existence of quanta is well es-
tablished. Understanding why they diff
fer so much is not so easy. These diff
ferences in effect may be clarified by
such discoveries as angular momentum
and molecular spin.
Among the well recognized particles
of solid" substances, molecular spin is
an important attribute. It has to do
With the supposed ceaseleSs motion of
the e,ectron and protons that compose
ta 1gible tn rgs.
To define molecular spin of a particle
Is like saying man that he is white
or he is Mcngolicn. A difference in
spin may make fully that degree o. diff
ference in thu character and the chem
ttal action Of MOSQUE.