The twentieth-century physicist Paul Dirac made a significant

UNDERSTANDING THE INTENDED MEANING

By breaking the sentence in the following manner, we can best derive the intended meaning:

The twentieth-century physicist Paul Dirac
made a significant contribution to his field with the Dirac equation,
a unification of all physics since Einstein
as well as
a glimpse of a series of discoveries that would come to revolutionize science.

• The author wants to tell us about the significance of Paul Dirac’s contribution to the field of physics, a contribution made by his Dirac equation.
• This Dirac equation was a unification of all physics since (the time of) Einstein
• (As well as)
• The Dirac equation was a glimpse of (a kind of precursor to) a series of discoveries that would come to revolutionize science.

Choice A is grammatically correct and conveys a logical meaning.

ANSWER CHOICE ELIMINATION

Choice B
The twentieth-century physicist Paul Dirac made a significant contribution to his field with the Dirac equation, a unification of all physics subsequent to Einstein and also his glimpsing of a series of discoveries that would come to revolutionize science.

• The construction implies that the Dirac equation is “his glimpsing of….” – illogical.
• “also” with an “and” here is redundant

Incorrect Choice

Choice C

The twentieth-century physicist Paul Dirac made a significant contribution to his field with the Dirac equation, a unification of all physics after Einstein and glimpsing as well series of discoveries that would come to revolutionize science.

• The above construction is meaningless – “glimpsing as well series of discoveries” is nonsensical.
• The construction implies that the Dirac equation is “glimpsing as well….” – illogical.

Incorrect Choice.

Choice D

The twentieth-century physicist Paul Dirac made a significant contribution to his field with the Dirac equation, unifying all physics from Einstein forward and also a glimpse of series of discoveries that would come to revolutionize science.

• In this choice “unifying” is a modifier preceded by a comma. In GMAT this construction means the “ing” modifier is modifying the verb in the preceding clause.
• So here “unifying” is modifying the action “made”. So, the meaning here is “Dirac, by making a contribution, unified all physics…” – this meaning is different from the intended one.
• “from Einstein forward” is a very awkward construction
• “also” with an “and” here is redundant.

Incorrect Choice.

Choice E

The twentieth-century physicist Paul Dirac made a significant contribution to his field with the Dirac equation, unifying all the physics done since Einstein as well as his own glimpsing of series of discoveries that would come to revolutionize science.

• The “unifying..” modifier error is the same as that in choice D.
• “his own glimpsing of” is awkward and meaningless.

Incorrect Choice