Great—this is a beautiful step, because these three ideas sit at three different scales of “where we are” in the universe.
I’ll show you a clean map first, then unfold it.
1. The three layers (one glance)
|
Concept |
What it is |
Scale |
Question it answers |
|
KBC Void |
local underdensity |
~100300 Mpc |
Are we in an unusually empty region? |
|
Laniakea Supercluster |
our gravitational basin |
~160 Mpc |
Which “cosmic region” do we belong to? |
|
Cosmic Web |
the universe’s structure |
billions of light-years |
How is everything organized overall? |
2. The
cosmic web
(the largest picture)
This is the fundamental structure of the universe.
What it looks like
- Filaments (threads of galaxies)
- Nodes (clusters)
- Voids (empty regions)
👉 Like:
a sponge / foam / neural network
Key idea
The universe is not uniform—it is a network of:
- dense regions
- empty regions
👉 Everything else (including us) lives inside this web
3.
Laniakea Supercluster
— our “cosmic region”
Named and mapped by Brent Tully and collaborators (2014).
What it is
- A gravitational basin
- Defined by how galaxies flow toward a common attractor
👉 We (Milky Way) are inside:
Laniakea (“immeasurable heaven”)
Key feature
- Galaxies move along filaments
- Ultimately drifting toward the Great Attractor
👉 So Laniakea answers:
Where are we flowing?
4.
KBC Void
— the controversial local condition
Proposed by Ryan Keenan and colleagues (2013).
What it claims
- Our region may be:
- less dense than average
- surrounded by denser regions
👉 Not a structure like Laniakea
👉 But a condition of the space we inhabit
Key question
Are we in a cosmic “hollow”?
5. Now put them together (this is the key)
Layer 1 — Cosmic Web
👉 The whole structure
- filaments
- nodes
- voids
Layer 2 — Laniakea
👉 Our local flow system
- a basin within the web
- defined by gravity
Layer 3 — KBC Void (if real)
👉 Our local density condition
- possibly underdense
- embedded within Laniakea
6. A simple analogy
Imagine:
Cosmic web
= the entire landscape
(mountains, valleys, rivers)
Laniakea
= the river basin you belong to
(where water flows together)
KBC void
= whether your house is in
a valley or a hollow
7. Where are
we
(precisely)
- In the cosmic web
- inside the Laniakea supercluster
- possibly near the center of a mild underdensity (KBC-like)
👉 So:
We are not at a center
but in a flowing region within a structured void-filled network
8. One sentence summary
The universe is a web;
we belong to a flow within it;
and we may be sitting in a slight hollow of that flow.
9. A very light translation into your language
- cosmic web → 萬物流轉的結構
- Laniakea → 江水之勢
- KBC void → 水勢中的一處空隙
👉 So:
我們不在中心
我們在流中
而流中，亦有空
10. Final quiet line
Not at the center,
not even in a fixed place—
but in a current,
moving through
a web that is mostly empty.
If you like, we can go one step further (this will be fascinating for you):
👉 map
cosmic web / void / flow
onto
your 巨石 × 江水 × 為岩中花樹所見
—that connection is surprisingly precise.
