On the Possibility of a Contact Analogue of the Kirby Move of Type 1 for Contact Surgery Diagrams

Concetti Chiave

While a contact analogue of the Kirby move of type 2 exists for contact surgery diagrams, the existence of a type 1 analogue remains an open question, with this paper outlining the necessary conditions for such a move and exploring potential candidates.

Sintesi

Bibliographic Information:

Deep, P., & Kulkarni, D. (2024). On A Potential Contact Analogue Of Kirby Move Of Type 1. arXiv preprint arXiv:2407.04395v2.

Research Objective:

This paper explores the possibility of defining a contact analogue of the Kirby move of type 1 for contact surgery diagrams, aiming to establish a parallel to the existing framework in the topological category.

Methodology:

The authors analyze the topological conditions required for a contact surgery diagram to be a potential candidate for a contact Kirby move of type 1. They define two collections, C1 and C2, of contact surgery diagrams satisfying these conditions and then proceed to analyze the viability of each collection.

Key Findings:

• The authors demonstrate that no contact surgery diagram in collection C1 can satisfy the necessary conditions for a contact analogue of the Kirby move of type 1.
• Within collection C2, they eliminate a specific type of contact surgery presentation, narrowing down the potential candidates.
• The remaining candidates in C2 are identified as contact surgery diagrams on a single Legendrian unknot with a specific framing, denoted as "tight."

Main Conclusions:

While the existence of a contact analogue of the Kirby move of type 1 remains an open question, the authors identify a specific type of contact surgery diagram as a potential candidate. However, they also demonstrate that this candidate cannot be realized as a ribbon move, leaving the question of its validity as a Kirby move unresolved.

Significance:

This research contributes to the understanding of contact surgery diagrams and their relation to Kirby calculus, a fundamental tool in 3-manifold topology. The potential discovery of a contact Kirby move of type 1 would have significant implications for the study of contact 3-manifolds.

Limitations and Future Research:

The authors acknowledge that the identified potential candidate in C2 requires further investigation to definitively determine its validity as a contact Kirby move of type 1. Future research could focus on exploring alternative approaches to defining such a move or investigating the properties of the identified candidate in more detail.

Statistiche

tb(K) = -m, where tb(K) represents the Thurston-Bennequin number of a Legendrian knot K.
Contact framing n = m ± 1 for potential Kirby move candidates.
Contact (m+1)-surgery diagrams are considered for m ∈ N.

Citazioni

"In this note, we explore a potential analogue of the Kirby move of type 1 in the setting of the contact surgery diagram."
"We would like to mention that Vera V´ertesi is working on finding out a complete set of contact Kirby moves for contact Kirby calculus."

Approfondimenti chiave tratti da

On A Potential Contact Analogue Of Kirby Move Of Type 1

by Prerak Deep,... alle arxiv.org 10-22-2024

https://arxiv.org/pdf/2407.04395.pdf

Domande più approfondite

How might the development of a complete set of contact Kirby moves impact the study of contact structures on higher-dimensional manifolds?

While the paper focuses on contact 3-manifolds, the question hints at a broader and more challenging problem: extending contact Kirby calculus to higher dimensions. Here's a breakdown of the potential impact and challenges:
Potential Impact:

Higher-Dimensional Contact Surgery: A complete set of contact Kirby moves in 3D would provide a blueprint for defining and manipulating contact structures on higher-dimensional manifolds via surgery. This could lead to:

New Constructions: Discovering novel examples of contact manifolds in higher dimensions, which are currently not well-understood.
Classification Results: Potentially classifying contact structures on certain classes of higher-dimensional manifolds, analogous to Smale's h-cobordism theorem in smooth topology.

Connections to Symplectic Topology: Contact manifolds are naturally connected to symplectic manifolds (even-dimensional manifolds equipped with a closed, non-degenerate 2-form). A higher-dimensional contact Kirby calculus could shed light on:

Symplectic Fillings: The problem of finding symplectic manifolds whose boundary is a given contact manifold.
Lagrangian Submanifolds: Understanding special submanifolds within symplectic manifolds, which are closely related to Legendrian submanifolds in contact manifolds.
Challenges:

Increased Complexity: Contact geometry in higher dimensions is significantly more intricate than in 3D. Finding a complete set of moves that capture all the topological operations needed to relate different contact structures will be a formidable task.
Lack of Analogues: Some key tools used in 3D contact topology, like open book decompositions, do not have direct analogues in higher dimensions. New ideas and techniques will be needed.
Analytical Difficulties: Higher-dimensional contact geometry often involves sophisticated analytical tools from partial differential equations and symplectic geometry. Translating these tools into a combinatorial framework like Kirby calculus will be non-trivial.
In summary, while a complete set of contact Kirby moves in 3D would be a significant achievement and might offer hints for higher dimensions, extending the theory faces substantial challenges. New insights from both topology and analysis will be crucial for progress in this direction.

Could there be alternative topological frameworks beyond Kirby calculus that might be more suitable for defining a contact analogue of the Kirby move of type 1?

Yes, there are alternative frameworks that might be more suitable than Kirby calculus for defining a contact analogue of the Kirby move of type 1. Here are a few possibilities:

Open Book Decompositions: As mentioned in the paper, Avdeck showed that ribbon moves on open books provide a complete set of moves for contact 3-manifolds. Open books offer a more inherently "geometric" perspective on contact structures compared to Kirby diagrams. A contact Kirby move of type 1 might have a more natural interpretation in the language of open books.
Heegaard Floer Homology: This powerful invariant in low-dimensional topology has a "contact flavor" through its connection to Legendrian knots. It's conceivable that a contact Kirby move of type 1 could be understood as an operation on Heegaard Floer homology groups, potentially leading to new invariants and classification results.
Contact Handle Decompositions: Similar to handle decompositions in smooth topology, one can build contact manifolds by attaching "contact handles." This framework might provide a more direct way to study contact surgeries and could offer a different perspective on Kirby moves.
Legendrian Surgeries along Tangent 2-Planes: Instead of focusing on framed Legendrian knots, one could consider surgeries along tangent 2-planes to the contact structure. This approach might lead to a more refined understanding of contact surgeries and could reveal new moves beyond the classical Kirby moves.
Reasons for Exploring Alternatives:

Geometric Intuition: Kirby calculus is inherently combinatorial, while contact geometry is deeply rooted in geometric structures. Alternative frameworks might offer a more intuitive understanding of the geometric changes induced by contact Kirby moves.
Computational Advantages: Different frameworks might have computational advantages for specific problems. For instance, Heegaard Floer homology has been remarkably successful in proving the existence and uniqueness of tight contact structures.
Generalizability: Some frameworks, like open books or contact handle decompositions, might be more readily generalizable to higher dimensions, offering a path towards a higher-dimensional contact Kirby calculus.
In conclusion, while Kirby calculus has been incredibly successful in smooth topology, exploring alternative frameworks is crucial for developing a comprehensive understanding of contact Kirby calculus, particularly for defining a contact analogue of the Kirby move of type 1. These alternatives might offer deeper geometric insights, computational advantages, and better prospects for generalization.

If a contact analogue of the Kirby move of type 1 were to exist, what new insights could it offer into the relationship between smooth and contact topology?

The existence of a contact analogue of the Kirby move of type 1 would be a significant development, potentially offering valuable insights into the interplay between smooth and contact topology. Here are some possible implications:

Finer Topological Control: The standard Kirby move of type 1 allows for the introduction or removal of a sphere with trivial normal bundle. A contact analogue would imply a way to do this while preserving the contact structure. This suggests a finer level of control over the topology of contact manifolds compared to smooth manifolds.
Constraints on Contact Structures: The lack of a straightforward contact analogue of the Kirby move of type 1 in the paper highlights a key difference between smooth and contact topology. The existence of such a move would impose constraints on which smooth surgeries can be realized as contact surgeries, providing a deeper understanding of the relationship between smooth and contact structures.
New Invariants of Contact Structures: The contact analogue of the Kirby move of type 1 could lead to new invariants of contact structures. These invariants could help distinguish contact structures that are indistinguishable by existing invariants, refining our ability to classify contact manifolds.
Connections to Symplectic Filling Obstructions: The existence of a contact analogue of the Kirby move of type 1 might provide new tools for studying symplectic fillings of contact manifolds. For instance, it could lead to new obstructions to a contact manifold being the boundary of a symplectic manifold.
Bridge Between Gauge Theory and Contact Topology: Kirby calculus has deep connections to gauge theory through the work of Donaldson and others. A contact analogue could potentially bridge gauge-theoretic techniques and contact topology, leading to new insights and applications in both fields.
Example:
Consider the case of surgeries on knots in $S^3$. The standard Kirby move of type 1 implies that any two surgeries on a knot with framings differing by 1 are smoothly equivalent. However, the paper demonstrates that this is not true in the contact category. This difference highlights the subtle interplay between smooth and contact structures and suggests that a contact analogue of the Kirby move of type 1, if it exists, must encode information about the contact structure in a non-trivial way.
In conclusion, a contact analogue of the Kirby move of type 1 would be a powerful tool, providing a deeper understanding of the relationship between smooth and contact topology. It could lead to new invariants, shed light on symplectic fillings, and potentially bridge the gap between gauge theory and contact topology. However, as the paper demonstrates, finding such an analogue is a delicate task that requires a careful consideration of the interplay between the smooth and contact structures.