• Keine Ergebnisse gefunden

Exercises for discussion in the exercise class on 06.12.2018

N/A
N/A
Protected

Academic year: 2021

Aktie "Exercises for discussion in the exercise class on 06.12.2018"

Copied!
1
0
0

Wird geladen.... (Jetzt Volltext ansehen)

Volltext

(1)

Singularities, Monodromy and Zeta Functions Blatt 7

Exercises for discussion in the exercise class on 06.12.2018

Aufgabe 1:

Let X = {(x

1

, ..., x

n

)|f

1

(¯ x) = ... = f

k

(¯ x) = 0} be an affine variety over Z and X(R) = {(x

1

, ..., x

n

) ∈ R

n

|f

1

(¯ x) = ... = f

k

(¯ x) = 0} the set of R-valued points of X .

Show that X : R 7→ X (R) induces a functor from the category of rings to the category of sets.

Hint: How should one write X(f ) for f a ring homomorphism?

Clarification: Here rings are (by definition) commutative and unital; morphisms in the category of rings preserve 1.

Aufgabe 2:

Verify that X := {x|v(x) = 1} is a uniformly definable set in terms of Definition 1.5.5.

That is, write out X in terms of affine algebraic varieties, ( Z

p

)

p∈P

and the operations of co-ordinate projection, cartesian product and boolean combination.

Aufgabe 3:

Let X := {x|v(x) ≥ 0 ∧ ∃y : y

2

= x}.

In the lecture we saw that µ

p

(X( Q

p

)) =

2(p+1)p

for all p ≥ 3.

(a) Calculate µ

2

(X( Q

2

)).

(b) Write down a single Z ∈ C

0

such that ev

p

(Z) = µ

p

(X ( Q

p

)) for every prime p (including 2).

If you’re too lazy for (a), you can denote the rational number µ

2

(X( Q

2

)) by r and solve (b) with that.

Course website: http://reh.math.uni-duesseldorf.de/~internet/Zeta_WS18/

Referenzen

ÄHNLICHE DOKUMENTE

Exercise 3, Ch.4: How large is the hierarchically aggregated cube (without base table) for an aggregation up to the levels of the prefixes of calls, geographic 100*100 m squares

Reduce the dimensionality of the fact table by exploiting the fact that the location of a mobile phone user usually can only be determined by the current cell.. Make sure that

Reduce the dimensionality of the fact table by exploiting the fact that the location of a mobile phone user usually can only be determined by the current cell.. Make sure that

For the following code fragment, count the number of times the function f is invoked and express this in Θ -notation as concisely as possible.. For the following code

A variant of Herbrand’s Theorem reads: A formula in first order predicate logic without “=” is satisfiable if and only if it has a Herbrand model.. a) Present a satisfiable formula

• Atmospheric neutrino oscillations confirmed by long-baseline accelerator neutrino experiments... 31: The zenith angle distribution for fully-contained 1-ring events,

You have to ensure that you have copied the source code of your solved exercises to the server before the exercise class starts.. If necessary, ask your tutor how to copy files

In this exercise we want to show that the model construction for FO 2 -formulae from the lecture is optimal in the following sense: in general it does not suffice to take only